I took a new to me rifle to the range this morning. (I have already been several times finding a load the gun likes.) It's a 308 that likes the Sierra 165 HPBT Gameking seated out as far as I can. 47 grains R15 is giving me 2770 with a low spread. I also shot another known load from a different rifle. The chrony is on.

Anyway, now I found a load it likes, today was the day to check drop. At one hundred yards, I'm two inches high. At two hundred yards I am right on. The computer says with this bullet, this temp., this altitude, and at this speed, I should be about 9 inches low at three hundred. I shot a good group at three, but it was 20 inches low instead of nine!
(I'm shooting pretty level, and at three hundred it wouldn't make that much difference anyway.) The group from my other rifle was right on drop wise.

I tried again. My second group was in my first group, still 20 inches low instead of 9. These were on a fresh target. I'm not confusing groups or aiming references.

Any ideas? If it was a scope problem, it wouldn't be grouping so well at 100 and 200, right? (Both rifles have 2.5-8 Leupolds.)
The scope on this rifle has less than two hundred rounds through it and it seems to track well. Could it be a paralax problem? That seems way too big of a change to attribute it to paralax to me. Plus, the group sizes are still good.

The barrel is floated. I'm trying to keep it in the bags with the same pressure (death grip is what this rifle prefers) each shot. Whenever I've tried a different grip, my groups get much bigger.

This rifle was really finicky and hard to find a load for. I finally found one, and it is grouping well, it's just 11 inches low! I didn't even try to go out farther. The wind was picking up and I was out of time.

I don't just want to live with 20 inches of drop with a two hundred yard zero. I want the rifle and load to line up with the Boone and Crockett reticule in that scope, so I need to figure out what is going on. (The scope was painted to match the rifle.) I shot with the center of the reticule to measure drop. For the load to line up with the scope reticule, I need it to be at the nine inches low it should be at at three hundred. (I'll be using the small traingle setting with this load.)

I've shot a lot at longer ranges and I've never seen this before. A couple inches off, sure, all the time. Eleven off the chart at 300, never.

I had planned on taking this rifle on a pack in bear hunt this weekend. I can take the other rifle so it isn't a big deal, I've just never seen a load be so far off before. Before this, the biggest difference I've seen was three inches from the chart at 300 yards.

I don't have a clue what might be causing this. Any help would be appreciated.

I have NO idea what is going on there! I am pretty sure that the bullet is NOT actually dropping 20" below line of sight between 200 and 300 yards, however. 9" to 10" would be about right based on my experience with a .308 and the .300 Savage. With 150s at 2600fps in my .300 Savage and a similar sight in to yours (2.5" high at 100 yds), I get around 12" of drop at 300 yards. Something is not what it seems....I'll be interested in the answer when you do figure it out! It is challenges like this that make the hobby interesting.

damned if I can explain that.

The only thing that immediately occured to me is that 20" would be about the drop below POA at 400 with that load and sight-in. But it was shot at 300....

Apparently the mysteries of the universe are uending.

Lee24 could solve this

Dang! Where is that boy when you really need him?

He's probably off hunting brown bear with his South Carolina .375. Or maybe competing on the Swedish bikini team.

I think he hunts them with his bare hands...

Some times the imagination can be a horrible thing. Thanks, John. Bear

I was thinking along with MD about 400 yards. That is extremely curious.

Bullets got mixed up. You're shooting ones heavier than you think?

That's an interesting problem you have there.

Ella

I have the Federal Ballistic chart on my computer. I looked it up, the .308 with 165 bullets at 2700 FPS. With a 200 yard zero, POI is -8.8 inches at 300 and -25.8 at 400 yards.

This is comparing two seperate trajectory charts, yours and Federals, and they are almost identiclal. Actually, all the 165-168 grains bullets are within an inch or two of your calculations.

I do not know the answer, either. Did you do the cronographing on the same day as the drop tests? Is the ammunition the exact same thing for both tests.

I think I would start by remeasuring the 300 yard distance, and also testing the loads again over the chonograph, and doing the drop test at the same time. Also, re-recheck your 100 and 200 yard zero.

I have used these trajectory charts for many different calibers, out to 500 meters, to figure drop, and they are always pretty close.

I agree. I shoot a lot of 308 rounds at 300 yards and 9" drop relative to a 200 yard zero is mighty close for a variety of loads.

The extra drop should be way too much to attribute to parallax as well.

Unless the OP accidentally went to the 400 yard berm I don't have an explanation.

Seen Nosler Partitions shoot great at 100yds and groups fall apart at 200 and 300yds. I have shot that bullet in a number of 30/06s, 300WM and 300rums and did not have the same problem. According to the Sierra data you are about four grains above max for that bullet in a 308Win. with RL 15. Not saying that is the problem but I would try a different powder. If the problem continues, switch bullets.Rick.

Am I understanding correctly that you did not turn the vertical adjustment on the scope between the time you sighted in at 200 yards and the time you shot at 300 yards (you just shot higher on the target and the impact was 20" below point of aim)?

I would re-zero the scope for 100 yards and then see what I got for drops at 200 and 300 yards without touching any adjustments on the scope. I know that checking the trajectory at 100 yards for a 200 yard zero should be doing the same thing, but if I can't figure something out, I change something for which the effect of the change should be well defined to see if that sheds any light on the problem.

As well he should be, after all he did invent it.

Is it really 300 yards? Might the BC you ran on the calculator be a...cough...fantasy? In the absence of anything else concrete I'd be suspicious of the advertised versus real BC. Marketing and truth are seldom found in the same bed.

How high is your scope above bore center line?

I shoot that same bullet at lower speeds and don't get anywhere near the reported extra drop. It's not the BC of the bullet.

DigitalDan - That's one reason I suggested zeroing at 100 yards and seeing what the drop is at 200 and 300 yards. A quarter or even half inch difference in trajectory at 100 yards might be lost in the group size (even with a good three-shot group), but the difference will be more noticeable if you shoot at 200 and 300 with a 100-yard zero.

.............ID,,,,,,,That is highly damned peculiar and I can certainly understand your concern. If your chrony is correct, the bullet weights are correct (no mix ups) and the bullet BCs are correct for the bullets you are using, then you shouldn`t have an 11" difference in the bullet drop with a MV of 2770 fps. Something is going on here between the 200 and 300 yard mark. It seems as though, like your shooting into a down range wind shear or into a substantial headwind that you don`t feel, but that is nevertheless downrange from your bench???

Possible ogive defects with this particular lot of bullets you`re using, which in turn may cause excessive bullet drag between 200 and 300 yards?

The first thing I`d do if it were me, would be to try another 165 gr bullet brand using the same identical charge, powder, COAL etc and etc and then see what happens. If the results are NOT the same, and you do get the normal 9" drop between 200 and 300 yards, then that would mean there was something wrong with the lot of Sierras you were using.

Imo, the first thing you need to do is look for consistencies, or hopefully in this case an inconsistency by changing the brand of bullet while maintaining the same bullet weight and roughly the same BC.

I`ll be very curious too see what you find out! But I`d start with a bullet change first.

Sunspot activity.

yeah, but even a rock with a parachute wouldn't drop that much more between 200 and 300 yards! Well, I might be exagerating, but you get the idea.

As an added thought, I`m sure your 200 and 300 yard distances were correct too? Were your distances calculated by a rangefinder in good working order?

Scope zeroed in correctly at 200 yards and nice and tight?

If all the tees are crossed and the eyes are dotted and there are or were no drastic down range wind flurrys, then I would go back to the bullet itself and start with a bullet swap!

I think I would try to borrow another chronograph, either that or you loaded the wrong powder by mistake? SWAG
whelennut

I'm the guy who started the thread. I just went downstairs and pulled several bullets. It is the right bullet. It is the right powder and charge weight.

Rick, thanks for the heads up on being that high over book with that load. I thought I read 47 was max with that load. (Reloader data on their net site.) I worked up to it, and the hotter it got, the smaller the groups got. I'll back off so I don't get myself this summer when it gets hot. So far, no sticky bolt lift and the primer pockets don't feel loose. Primers look fine, too. I get the same speed with the same components with 165 SSTs, so didn't think too much of it.

Digital Dan, it's 300. That bench at the range is for the 200 and 300 yard boards. The 400 yard section is down the road. The scope is maybe 1.5 inches above the bore. I didn't measure it, but it's low .

RR, I didn't touch the scope adjustments. I had put up two big pieces of butcher paper with an aiming point on the top. I hold on that aiming point. I always do this to measure drop.

Guys, all I can think is that the reticule cell shifted, or went "sproing", between my 200 yard shooting and the 300. I know that is a huge coincidence, but that is all I can think of. I'll try to head back out Wednesday and confirm my 200 yard zero. I should have done it before I left but I was out of time and about ready to start pulling my hair out. Before I moved to 300, I shot two, three shot groups that were both just over two inches and dead in the bulls eye. The gun wasn't dropped or anything like that.

Guys, I don't think this is a bullet problem. These loads are grouping great. If the wind dies down, it has been under an inch at 100 and at two inches at 200. If I do need to switch bullets, do you have any other AFFORDABLE bullets I should try? I've already read the "Good 308 loads" in the reloading forum. If I need to slow this bullet (the 165 Sierra HPBT Gameking) down four grains (200 fps?) to be safe, this bullet, with it's low b.c., isn't gong to line up with the B and C reticule in the scope at all.

I don't want to try the old Speers because they are going to be replaced, and I don't see the new ones out yet. I've heard lots of good things about the Horn. 150 flat base, but I'm thinking with that sectional density it would be too light for elk. I did try the 150 SSTs, thinking I could use the interbonds for elk and the SSTs for playing. The gun liked these the least, at about two inches at 100 yards, with R15, R17, and H4831. I tried The 165 interlocks and SSTs. All of those bullets, with the other components, are 1.5 to two inch loads. I'm not happy with that. The gun groups the 180 interlocks great, but they are only leaving at 2580. I think impact velocity would be too low for expansion on a longer shot.

But, again, I don't think it is a bullet problem, I'll head back out. I've never seen this before and am wondering what dumb thing I'm overlooking or did wrong!

Thanks for the help and I'll post what I find after my next time out.

I've seen stranger coincidences than that, a re-shoot is definitely in order. I can't imagine what could've caused so much drop at 300 short of a major transient in the gravitational constant of the universe. Or it could be those immodest earthquake causing women that some Iranian cleric was gassing on about.

call rich matcholz at serria ask him and explane your problem there great to work with .They put you in the right place to go and what up with your set up tell him rudy sent you from mi .Goog luck. 400 yard should drop around 24 inch an 8.5 or so with 300 yard with 200 yard zero

Understood and I agree.

You need to know what the scope height is. Otherwise is skews the ballistic calculation. Realize this sounds like quibbling but it really isn't. 1.5" is a standard reference..you say "low"...might not be the same thing and having a lower scope will have the effect you're experiencing as I understand it.

My money is on the bullets not all being the same type, ie 150gr mixed with 165gr weight. Either that or they are mixed up with guilding metal / copper only bullets of the same shape & length. The only way to find out is to weigh all of the bullets but I'm betting on different weights due to inconsistencies in the amount of lead etc. in the bullet. Also, if these were non lead bullets mixed in with lead bullets, regardless of the shape and overall size they would act differently, especially at longer ranges. The fact that you are able to use a hotter load than usual for this weight of bullet would also be indicative that they are not lead or contain a less dense material than lead in the bullet. Finally being of lighter weight, they should drop faster at extended ranges.

Flower Child

A brief suggestion if one repeats the exercise. Try a series of shots with round one at 100, rnd 2 at 200, and 3 rd at 300. Repeat until one has 3 to 5 shots on each target. If one shoots exclusive groups at seperate targets, then each target is an independent event. The series approach will at least remove that aspect from your trial.

Buffalo's me completely. Please post your eventual findings.

ID,

What scope mounts are you using? I remember reading an article where the fellow was testing various rifle and load combinations at 100, 200, 300, and 450 yds. The writer had the opposite puzzle. He discovered his .308, shooting a 150 grain bullets at 2800 fps mv. was +1 at 100, +1.5 at 200, -5 at 300, and -31 at 450 yds. The 300 H&H in the test with 165 bullets at 3000 fps mv. was +2.5 at 100, +1.25 at 200, -5 at 300, and -31 at 450 yards. His hypothesis was the scope on the rifle was not mounted parrallel to the barrel. I don't know if that was the case and the cause and I would rather have his "problem" than yours. When you mounted the scope did you check and lap the rings if they needed it?

Probably going to find somthing with the sight setting being off. I looked back through notes on different M1a's and found the 300 yd setting to be 3 min. (clicks) up from 200 yards. That's with anything from 147 gr south african ball (cheap stuff) to 168 smk's.

IDMilton,

I had the identical problem with my Ruger M77RS 35 Whelen. My handloads of 59 grains Re15 over the Speer 250 grain spitzer would shoot about 2-1/2 inches high at 100 yards, and zero at 200. At 300 they were low off the target board. I never did figure out exactly why it happened, but I did figure out how to fix it.

When the problem occurred, the Whelen barrel was free-floated. I was going through a "free-float" phase at the time and floated everything I owned. In desperation I test-fired the rifle with shims installed between the forend and barrel and the problem went away. The 300 yard drop was now closer to 10 inches. So I made the shims permanent and that was the end of the problem.

Incidentally, that Ruger barrel is of standard contour, and a 35 caliber hole doesn't leave a lot of steel, particularly at the muzzle. Consequently, the upward pressure exerted by the forend on the "flexible" barrel raised the POI considerably.

The actual cause of the problem is left to speculation. The theory I came up with says that the "flexible" barrel vibrated quite a bit and released the bullet with a pitch problem (not quite like Randy Jackson complains about). I suppose the nose of the bullet was pitched downward and planed downward. Can anyone prove me wrong? Mike Venturino wrote about a 308 rifle he had that exhibited the opposite problem. He said that rifle shot a bunch flatter than it was supposed to. Now that is a good problem to have. If we could figure out how to repeat that "problem" at will we might have something valuable.

I suggest you install temporary shims for about 5 pounds of upward barrel pressure, and test fire. If it works, make the shims permanent.

Good Luck!

SteveNO will be soooo jealous.........



Casey

I would still try another chronograph.

Velocity causes bullets to shoot flat or otherwise. I would also try another bullet of the same weight and compare the two. Something like a Nosler BT or TSX if you have any would be a good test.

JW

So velocity 100 or 200 fps slower is going to more than double the drop at 300 yards? Not hardly.

Double checking adds value to the research. Criticizing double checking does not.

JW

ID Milton: Did you use the exact same type of rest for your 100 yard zero,that you used when shooting at 200-300? Any changes at all to your positions or the way you were holding the rifle when you shot at 100,200 and 300?

I think Big Redhead is nudging around the source of the problem....

A buddy came here from NY with a Rem 700 KS Mountain rifle chambered for 300 Win Mag. We clocked his 165 Partition handloads at 3100 fps,zeroed from sandbag rests to be 3" high at 100 yards.The rifle shot well.

But at 400 yards,after he had gone to a field prone position,POI was about 20" low.....I knew from past experience with that load,that it should have been about 12" low.He was puzzled, and I told him he had a "false" zero at 100 yards.Because he had a bedded barrel,the rifle was hitting high by bouncing off the firm bags at 100,causing the POI to be high. When he went to the 400 yard line, held the rifle in his hands,this "bouncing" effect was gone,the rifle assumed a different vibration, and hit lower than it should relative to its 100 yard zero,given its' velocity..

The solution in his case was to free float the barrel,which eliminated the bouncing,and his trajectory became more "normal".

But ID Milton has a free floated barrel;so did Big Redhead,so I guess what it all points out is that you cannot depend on trajectory tables to tell the "truth" about YOUR rifle and the only way to determine true POI at various ranges is to shoot at those distances. I guess it also points out that there is some kind of relationship between barrels and forends that can affect POI as well under certain circumstances.

That is what I am thinking also.

The higher that the scope is mounted the flatter the trajectory APPEARS to be,
according to an old Outdoor Life article by J O'connor.

My .30/06 has extra low mounts and shows about 14" of drop at 300
when sighted 2.5" high at 100 yards.

That is not unusual, your only talking about 2 inches difference, 11 inches as opposed to 9 inches, as I understand your post,

That can be written off as to the accuracy of your particular rifle that is technically viewed as a 300 yard group should be 3 times larger than your 100 yard group, but such isn't usually the case, as a matter of fact its usually much more and sometimes much less. The height of your scope can account for two inches at 300 yards very easily.

Also the weather can determine a certain amount of drop such as high humidity can cause more drop than Mountain air, updrafts in steep canyons can raise a bullet a foot at 100 yards in the Snake River Canyon of Idaho. I see this all the time shooting rock chucks..Too many reasons to list come into play...

The bottom line is you do not have a problem because you tested your rifle and didn't accept the printed word, so now you can hold two inches higher..:) I congratulate you.

That is the reason I always write for folks to check their rifles at 100, 200, 300, 400 and even 5 and 6 hundred if they can..If you KNOW where it shoots then you can hold accordingly, and hope you can dope the wind, and thats the hard part.

Ray,he's meaning 11" in addition to his 9" drop for a total of 20" of drop. I've never encounterd anything like he's describing..................................................yet.

Yes the scope height could contribute as well,but 11" more of drop is a lot...puzzling....

EZEARL,
Oooops, if thats the case then it cannot be, in which case he needs to get someone else to shoot his gun first of all, then if the problem still exists, check the bedding and if that doesn't work then a new barrel is the answer as the bullet is not maintaining stabilization out yonder where is should be settling down.

I agree with those who suggest a re-shoot where you shoot 100/200/300, one each and repeat. No reasonable amount of velocity error, scope height error can account for that difference from 200 to 300. JBM Ballistics says 2" high at 100 should put you on at 200 and 8-9" low at 300 (depends very slightly on elevation; i.e. a couple tenths of an inch variance). Something had to change prior to firing at 300.

I'm the OP. I definitely will do a reshoot. I couldn't make it out today, and it would have been ridiculous anyway. The wind is screaming and it is raining sideways.

The forecast is for the same all week. If it lets up at all, I'll try in the morning. If I can't get out in the morning, I won't be able to make it out till Monday. It is supposed to be 28 mph tomorrow morning, with guests. ((Zip 83440, with rain or snow, 39 degrees for the high.) With the wind like this, I don't think the groups will be too great!

All I can think of is that it is a scope shift. That would be a big coincidence, but it is the only thing that makes sense.
If I can't figure it out again, I'll try adding the pressure point as mentioned. If the pressure point doesn't fix it, I'll get back on here and ask some more questions!

The rings and bases are standard low steel Leupolds that came with the rifle. The scope was mounted when I bought it. I didn't take it out to lap the rings like I usually do. I did center the the windage adjustment in the scope, then I used the mount's windage adjustment to sight in (horizontally) the first time out, then I used blue Locktite on the windage screws. I planned on putting Talley extra-lows on it, but since the whole thing was painted before I bought it, I'd need to order the Aluma-Hyde. Two colors, shipping, and the rings adds up money wise, so I thought I might just leave it alone if it works. If we can't find the drop problem, I can try new rings next.

I measured the scope height above the bore. It's is 1 3/8", the same as my other rifle with the same scope. That rifle shot with the expected eight inches of drop at 300, which kind of negates the idea of wind for me.

Bob, it was the same rest. When I set up I set up on the far left of the 200 boards. When I shot 300, I shot the far right of those targets. Because of the way this range is staggered, I only needed to shift my rifle and sandbags a few inches on the same (concrete) bench.

AGW, I'll see if I can get a buddie's chrony, but the other rifle (a .260) was the same speed it usually is.

I'll post my results when I get back.

Thanks again for all the help.

Now these low rings is the front bell touching the barrel.This could be the problem .With a 40 mm bell I use high rings

I like Big Redhead's explanation, unless it proves wrong . I had a similar problem with a .30-06, whose bullets just wouldn't drop. With 125 grain Ballistic Tips, it was supposed 6 or 7 inches low at 300, but there was 0 drop between 200 and 300 yards. And we shot a lot to confirm what we were seeing. Shouldn't be, but the Mike Venturino and Big Redhead thinking seems to be on to something to me.

Short-range barrel accidentally installed at the factory.

ID please accept this in the most constructive way as I am by no means dumping on your rifle,but......270's end these conversations very quickly

ID I understand your frustration. I had the same type of drop mystery with a 7/08 and 400 yard targets. From a 200 yard zero it was suppose to be down about 19" @ 400 yards and what it actually shot was -30" @400. I decided not to use it for open area hunting.

If you are using the Leupold base with the windage adjustment, that could be your problem. I have had lots of trouble with those things. Trouble with elevation changes.

What happens is the windage adjustment screws ride up out of the dovetail slots, causing the rear of the scope to rise, and/or bend. This causes the rifle to shoot high, which is not your problem, but still, if the screws were not seated into the dovetails perfectly, they could have been setting high and moved to the lower, correct setting after you fired the 100 and 200 yard groups.

I suggest losening both screws, and also the rings. Position the ring in it's correct position, and tighten both windage screws firmly. Very firmly. This should position the rear ring in the proper position. Next, tighten the rings, again firmly, around the scope tube.

You can try to get the windage adjustment as close to center as you can with the screws, but be sure they are tight and positioned correctly to line up with the dove tail cut outs in the screws and base. Do the fine adjusting with the scope adjustments.

I won't use the things anymore. The idea seems sound, but it just doesn't work as it should all the time. There are much better mounting systems available.

You said you had another rifle. You might try switching scopes in the even the elevation adjustment has gone bad, but if you do, be sure tp position the rear base correctly, and tighten it very firm.

Just a thought, did you shoot all groups with the adjustment caps off/on or did you put the caps back on or off just for the final 300 yd group. Wondering if the elevation cap could have somehow torqued the erector or even contacted the top of the dial.

For the life of me I can't figure how barrel harmonics could create this. For a given load the bullet should exit the barrel at the same arc position regardless of how distant the target. Meaning the bullet impact might be lower or higher than expected but still adjusted with regard to overall trajectory in a standard fashion. It should have the same RELATIONSHIP to impact at 100 yds as 300yds. Make sense?

Another theory FWIW on the windage base adjustment. If you are adjusting horizontally with the big screws on the rear base you have to be bending the scope tube at least slightly at the front ring. That front ring don't turn just from moving the rear of the scope. That turn lock is tight. The only times I've adjusted in this way was to bore sight. I actually left the rear ring a little loose and turned the front ring with an open ended wrench. Then tighten the opposing screws while checking the sight picture.

This is the OP.

Everyone, thanks for the help. I just got back from the range. I found out what I was doing wrong.

Bob, and some others said it might be me or my bench technique. I didn't really listen because I usually feel I do well and am careful. When I got to the range this morning, I shot two hundred first. Still dead on.

Then I switched to the 300 yard target, and my group was at the exact nine inches of drop is is supposed to be at. I got ready to shim the barrel, but decided to step back look at things again.

This rifle is pretty new to me. It is A Kimber Montana. I noticed the pistol grip was pretty close to the "ramp" looking base of a new rear bag I got a few weeks ago.

I scooted the gun back in the bags (less than an inch?) and fired three more at the 300 yard target. I went to check the target and had a five inch (It's really windy today!) group, exactly 19 inches low instead of the nine it should be.

That means I've had three, sub 5 inch 300 yard groups, all about 20 inches low, because the pistol grip was hitting the rear sand bag during recoil.

I should have guessed this. I'm usually really careful about putting the rifle in the bags so it rides correctly. It looks like it is the lighter rifle with more recoil and the new rear bag design coupled with my carelessness.

I hope I didn't waste everyone's time with what should have occurred to me before I posted.

Thanks again for the help! I need to run but I'll check back later to take my medicine.

Good stuff, glad you checked back with us and good info for us all to keep in mind!

Thx
Dober

(side note, how's unit 69 doing for muley deer these days? and you can pm me if you'd rather)

ID, no apology necessary.
You actually deserve thanks for posting your situation, and the solution such that we all can learn from it.

I had a similar problem getting a Win 70 338WM to group consistently. I used a consistent benchrest technique. After buying every bullet, powder and primer available and floating the barrel, and lapping the rings and changing scopes,ad infinitum, all I had to do was move my front sandbag back, so that it was under the chamber. Now it shoots consistent groups from the bench- 1/2 to 3/4 round groups, depending on the load.

And I didn't even try a DONUT yet. Or BLUE tape.

No, that's chuck norris.

Thanks for the update. Sounds like mystery solved.

Fixed it for ya.
Actually, "hands" should be singular...he does this with one hand tied behind his back.

This has been an intreagueing post and glad to hear the cause identified and problem rectified. I dare say your experience will be a great help to many. I made a conecter between my front and rear rests and by indexing on the front rest have taken that problem out of my own equations. A simple solution is to use a piece of 1/4 in ply or custom wood and cut the base shape of the rear bag so it still sit flat on the bench and drill a hole that the rear screw base of the front rest can sit in. I found my unexplained shots out of expected group were much diminished by using this indexing plate. I still have to do everything else consistently though.

Von Gruff.

Thanks for reporting the solution, there's always something to learn or re-learn. Hate it when a thread is left hanging.

Thanks for the update. The suspense was killing me. And glad you got it solved.

Ella

I've gotten a lot good out of this thread. I was on the edge of my computer chair! There had to be a solution, but what was it? I shoot a Kimber 84M and will now be aware of this possibility.

And I'm the goofy bastard for not using a bench and shooting at paper.

Dober,

Unit 69 (Tex Creek,less than 15 minutes from my door and great country) is getting hurt by the wolves. There were four sets of tracks in there when we were picking up sheds in 2007. Kind of cool to hear them howling, but I know they are hurting the deer and elk numbers. There seem to be far fewer elk and deer now, and they seem more spooky and stay in the trees more. I think lots of them moved across HWY 26 and winter on the dry farms to get away from them. Now I hear there are more wolves and that there is a den between Tex and Willow.

There are very, very few big bucks on public land during the general season. Dpending on snow, they move in later. However, if it is an early/heavy snow year and if you can get the Nov. draw tag, it would be a hunt of a lifetime. LOTS of huge, heavy beautiful mulies. The downside is the odds of drawing are about one in one hundred. I put in for years and finally just gave up. The odds are so low I'm just wasting the draw fee.

If you just want to see lots of huge bucks for fun, head up past Ririe Reservoir after January.

I'm not worried about putting this on a public forum because none of us will ever draw a tag there!

I never said that....

This is one of those things that happens;similar to my pals experience with the 300 mag. Little things can effect POI and accuracy as well.And whi shooting from distance the way one would in the field is a jolly good proceedure.

IDMilton;

Next time you go to the 300 yard target,get off the bench.Go prone, using your front rest as you would a log or a pack in the field and cradle the forend of the rifle in your left hand;don't use a rear bag at all.

You won't be able to hold as steady that way as you would off the bench,but don't worry about that.Fire 3 shot groups as quickly as you can cycle. Let us know if that effects POI and group size. Good luck!

PS:Sometimes we are all guilty of assuming that,just because we benched a light sporter at various distances that we have the "whole story";this is only sometimes true and is why it is important to get the rifle off the bench and into your hands at various distances.Recent obsession with tiny groups is the culprit here and the reason that many stay married to the bench,and never find out what shooter and rifle are truly capable of under field conditions.

IDMilton,

Congratulations on your success, and thanks for sharing it with us.

Thanks guys.

Bob, I usually practice offhand, sitting, and prone,and prone over my pack. Since I haven't bought a steel plate, I shoot milk jugs and balloons and paper.

Because this is a new set-up for me, I wanted the smallest groups possible to accurately tell me real drop. The place I'm shooting now goes out to 600 and I practice prone that far. Not that I'd want to shoot a big game animal that far, but it's fun and makes the closer shots seem a lot easier.

You made a joke earlier in the thread about 270s. In the last three years I've sold three and don't have one now. A Ruger ultrailight that walked badly after two shots. I know that it is fine for hunting, but I like to shot a lot and didn't like that. I had a Hawkeye next. It was accurate and consistent but the finish would scratch off with my fingernail. It was a little heavy for packing anyway so off it went. Then I tried a Tikka in 270. When I figured it out it was amazingly accurate. I sent it down the road for a stainless MK2 '06 with the green laminate stock I found for a good price. It matched my boy's 260 compact, which was kind of neat,and it was really accurate with 180 Horn. BTSP, but all up it was 9 pounds four ounces. When I found this Kimber 308, I sold it. Life would have been a lot easier gun wise to just stay with one of the 270s, but it's kind of fun getting the new ones going.

Of course, now my kids are a little older and my wife finished school and will be going back to work, maybe next year I can get rid of that household rule I have about me not getting a new rifle without getting rid of one!

This could very well indicate why a seeminly easy shot at a game animal is a miss, or worse, a wounded animal.

Rifles, and also handguns have a tendency to shoot to a different POI, depending on how they are held and the position they are fired from, and also who is holding it.

BobinNH made this very clear.

I would be interested in knowing the POI at 100 and 200 yards when the rifle was positioned like it was for the 300 yard tests which impacted low.

My guess is that the 100 and 200 yard groups would be considerably lower than they were in the original testing.

ID, this quote proves beyond doubt that you are a hopelessly-afflicted rifle loony. Welcome to the club!

123: Yes, that was why I am interested in how the rifle does from a field prone position....academic exercise to keep us informed.

This is interesting! I have noticed a similar issue recently, only groups moving left-right, very little vertical spread. I recently bought a new rear sandbag (med height ears). This thread got me to thinking because the rifle that exhibited this has a cheekpiece - thinking maybe the checkpiece is hitting the ear of the rear bag differently shot to shot, group to group ....

For example, shot 2 groups recently only 0.5gr apart in charge. Both groups were right at an inch at 200yds, but 4-5" apart left to right, and I had to move the rear bag between groups because they were on different targets.

An oldtimer at my club,a savvy gent named Gordy who is now deceased,told me that with any rifle that is full-length bedded, with pressure points etc, you have to recheck all zero's,etc from different positions because of possible shifts in POI going from even(in some cases) firm bags to off hand.There is no reason that grouping won't be better or worse, or vary a bit,depending on bench technique, how we hold the rifle, what we rest it on etc.

I found over the years that some rifles displayed this tendency and some did not.For example, a pre 64 M70 300 H&H showed no shift in grouping or POI going from bags to a tight sling, even out to 300 yards and was deadly dependable.OTOH a light custom 257 Roberts I have demands that you man-handle it,draw it in tight and get a firm grip;when it throws a flyer at 300 yards, I know it was me holding it too loosely.

The reason I went to rigid synthetic stocks and floated cut rifle barrels back in 1980 or so,for rifles I traveled and hunted with,was that I found such rifles grouped very consistently, whether from bags or softer positions assumed in the field;and you wrap up in a tight sling as well and POI would not be effected in the least.

Whoever commented that not knowing a rifle's tendency to do these things was spot on when he commented about such behavior causing inexplicable misses in the field.

I saw something like this at the range last fall. The guy next to me was sighting in using a lead sled type rest and 4 bags of shot. He got it where he wanted it, then put the rifle and rest off to the side. Then he shot another rifle off sandbags. After that he went back to the first rifle and shot a group off the sandbags at the same target he started with. It grouped about 4 inches higher and right off the sandbags than off the lead sled. He started mumbling, and was going to adjust the scope, when I told him just for grins to try it off the lead sled again. POI went back to where his first group was...

kcn: All too common IME.....where a guy really can get screwed is if he is unaware of the problem......and then has one of those "inexplicable misses" and wonders "why"?

One reason for this is that a rifle starts moving in recoil before the bullet has ever left the barrel. It amazes me that you can get any kind of group at all unless the rifles moves the exact same amount in the exact same direction each time.

Light weight and heavy recoiling rifles are the most difficult to shoot consistantly. Also, the shooters size and how he or she grips the stock have a lot to do with it.

It is puzzling that we can get rifles to shoot and group as well as we do.

I know sighting in off sandbags, then taking a shot at a deer by resting your rifle forarm against a tree to steady it would more than likely affect the POI.

I don't know if y'all have noticed this , but practically ANY bullet at ANY velocity will have three times the drop between 300 and 400 yards that it has between 200 and 300 yards , assumiong a 200 yard zero .

The 20 in. drop the OP was getting would have grown to a 60 in. drop at 400 yards had he shot it there and had his technique been consistent .

Had he shot the 400 yard range , I'm betting he would NOT have had 60 inches of drop and would have known that the 300 yard dope was bogus .

I am glad you figured it out,because I had no clue and was curious myself as too what caused this.