I had to swap to a new powder and want a load at or around minimum powder charge. Shots are typically close and am using those ProHunters everyone know explode on contact.so.....


For some reason loads listed for the 260Rem with H4350 seems really odd to me . Quite the drop from 120 to 130's. Unusual.
Powder Bullet weight Min Max
H4350 120 43.5 46.5c
H4350 130 38.5 41.9
H4350 140 39 42


Hoping to get lucky I tried a load just under minimum for the 120 grain since it seemed high to start with.

I loaded 43 grains at three different seating depths .04" apart 3 each.

I have been very pleased using this method in the past with charges I had arrived at with charge ladder testing.



Will let you know how it goes. Flame away if you like

I have not run H4350 in my 260's but have used H414. I found the max powder charge for my rifle and then played with the seating depths. After doing that and seeing the results, I am a firm believer in seating depth "tuning" and have done it with several rifles since.

As a side note: I load 50 rounds with my desired charge to the same max length and take a RCBS Partner Press to the range with me along with a seating die and calipers. I start with shooting 2 shots groups. If they are an inch apart, nothing you are going to do will turn that into a .5 group. I then bump my seating depth on two more and try again, and continue until I get something that looks promising, then I bump another one or 2 to that depth and see if they group as well. I might try .003 deeper and see what that does and keep bumping it until it starts to open up. I find the sweet spot and come back another day and make sure the repeat. If so, I have my load, and I seat what remains of the 50 rounds to that length and I am good to go.

I do something very much like this. Having a micrometer seating die makes things go a lot more smoothly.


Okie John

If I get lucky I will have results Thursday morning for this 3 tier ladder test at min charge.

So have either of you heard the rule of using .04" increments? I read it here - think it was reposted from somewhere else. A few others said they used it t0o. I felt it quite a find. I would love to be able to load at the range as you do but alas... Dream is my own range with a shop a few yard from the bench.

Hey Okie John- I looked at the micro- seater dies- which one do you like- and how much $$$. I have standard CBS seater with the nut on top which is sort of a pain in the turret. I also have a the free spinning Lee. If I can find the right depth using the Lee. which is easier, I will set up the RCBS which seems more permanent. For me what helps having is the Hornady cam-lock bullet puller for when I over dial a depth. Super handy tool.

I made some dumb changes from believing the internet over my lying eyes. Would love to find some of my fav bullets again but as things are - working with what I got.

Use a Sharpie to make a stripe on the top of the Lee seater cap. It makes eyeballing reasonably even increments a lot easier.

Two world class shooters on seating depth adjustments. Erik Cortina uses .003" adjustments and Jack Neary likes .001" - .002" adjustments.
Some very good info here on reading groups.

tag

Great minds think alike. I am ahead of you on this one MAthman.. I get it dialed in with the Lee I may adjust the RCBS seater and tighten the nut down. Having the turret allows me to a have a choice of two seating dies because I don't use it for dumping powder on rifle loads. I only dump for pistols. .

Maybe I will try that .003 as a fine tuner after getting this ,04 test done.

Wish I could find thee original post here suggesting that.

The 0.040" seating depth increment comes from Berger Bullets. I've used it with others, particularly the TTSX. Complete waste of time and components doing 0.003" increments in a hunting rifle.

Tune your powder charge first (find optimum charge weight [OCW]) first, then fine tune the load with seating depth.

https://bergerbullets.com/getting-the-best-precision-and-accuracy-from-vld-bullets-in-your-rifle/

Sort of like applying the latest Formula 1 tuning tricks to the old '72 Town and Country wagon.

I do seating depth test similar to Berger’s method but use .025” increments rather than .040” because .025” is a full turn of my seating stem, and that’s easy. As Berger states, one of the increments will generally shoot significantly better than the others. Works well enough that I don’t usually even worry with the fine tuning. Also, very often, my best precision comes from loads WELL off the lands.

The group shown below is a 10 shot group from my hunting weight rifle about .110” off the lands. The COAL shown is actually the BTO including the Sinclair hex nut comparator, so subtract 1” for the true BTO.



This group is 5 shots at 900 yards from my heavy rifle with its preferred seating depth for this bullet .100” off the lands.



John

https://www.midwayusa.com/product/1012740357?pid=394708


Okie John

Good shooting John. As per usual. I generally don't putz around with seating depth, but focus more on OCW and finding the right node. I can see its usefulness with bullets that are picky about seating depth though. Those bullets like Barnes or Bergers or even the Nosler Accubond. I'm going to be messing with seating depth on the TTSX bullet I loaded up yesterday for my 7mm08. I'm not getting the accuracy I want with that pill, so on to seating depth experimentation.. We will see how that goes. I'm hoping for something promising..

Seating depth is something that, until recently, I had not given enough credit to. These last couple of load development sessions I actually used 10 shot groups per charge, .4gr apart. I took the best charge from that, and then loaded up 10 round groups with seating depth .025” apart. Just as Berger states, one of them was significantly better than the others and until I got to that depth, all the groups looked pretty much the same. The best depth gave the groups in the pics above.

I know it sounds like a lot of ammo to develop a load, but I’ve found that doing it this way gives me very consistent, reliable loads that I don’t have to go back and chase improvement with.

John

Good stuff John. Thanks for sharing.

I agree .003 is not feasible for me.
Hondo- your post reads like my experience and I normally test by weight first. Will be interesting to see if perhaps this is assumptive. .

I have had long COAL come back to bite me after discovering they are beyond magazine length. My 6mm Rem and 260 are both short on the magazine side.
I found some accuracy return after shortening to differing lengths. And thanks to who it was that sent me the link to the mic dies. Trying to accurately figure out what 1/4 or 1/2 turn of my current seating die relates is so trial and error .

I didn't get to shoot yesterday and am lamenting not being able to go today as it is crazy weather right now.

If one of those 3 lengths gets me close with my stab-in-the-dark charge weight I may go then visit.025 on either side of that weight. I know this is a bit of a longshot but when it is impossible to find powder this could turn out to be a good way to go.

Good news is no one telling me I am nuts.....yet.

Not saying all dies have the bullet seating thread pitch of 32 threads per inch, but if they/yours does, it is easy to figure how much you are moving the seating without a micrometer adjustment.
32 threads per inch equals .03125 thousandths per one full turn of the adjustment. A half turn of the adjustment would be .01563 thousandths of an inch and a quarter turn of the adjustment would be .0078.
You could always make your adjustments in about 1/3 turns and end up with close to .010 inch bumps in seating depths.

Most may already know that but maybe that will help for those that don't.

https://www.24hourcampfire.com/ubbthreads/ubbthreads.php/topics/11270854

My experience.

Pullit- man.....seems so obvious now- thanks my man! Course now folks will see me counting out loud as I flip my fingers one by one with that cross eyed stare at the ceiling every quarter turn.

Que Jethro Bodine - 8 gazinta 10.......
.
Pharmseller- encouraging....course I only loaded three depths. Over optimistic perhaps. Counting down till the range opens

I really like that idea.

Hi All... well....I already wrote my Fire buddy EFW to say I guess I would rather be lucky than good.

Went to new range. They couldn't figure out their software for me to pay to shoot. Another guy came and took over and was told you can not use your own targets in a manner that said you are an a-hole for thinking you could. You get a free crappy paper one or have to buy one of the other like the Birchwood Casey Shoot-n- see I use.. There is like a 100 yd parking lot and the only other guy parked so close to me I did not have room to pull my rifle case out. WTH ?? Then I realized I left my rifle rest at the house. CRAP . Then you get escorted more or less to the range. Happily I was only one at the 100 yd rifle but they make all three ranges go hot and cold at same time so year here a lot of Alpha range going cold, Bravo range blah blah...geez ..but I won't argue with safety.
So yeah...I am a little pissy at this point but it is a nice day and I am getting to shoot. In truth the RO's couldn't have been nicer. All I had was a sweatshirt to roll up and use. Benches are oddly low and 2x4 wood seats they made wobble but ....I was happy to actually be pulling any trigger after such an interminable time.

Took my new mild H4350 load at thee depth, 3 each.

You ain't gonna believe me but this was my first three shots.
That hole on right was my first two shots so I either one -holed them or missed completely.


Second group was a tight one inch triangle and here was my third at the longest depth.


I was out of ammo and happy enough the last load was already close to being centered that I adjusted to clicks to right (oh no- its a Leupold) and thought I would just load up a few rounds of that for hunting. I may revisit first depth again- or I may try + and - .025. Every feel almost sad because EVERYTHING worked? I mean I almost don't know where to tinker.

So far ....kind of liking the Hogdgon.

Score one for seating depth ladder testing !

Ahh it never works, I was told on here all I did was find an accuracy node. Not a perfect load by charge or science. I called BS due to the fact 54 grains RL22 and a 110 AB in 25.06 was a max charge. Guess I should have went 55-56. Anyhow 25 shots varying seating depth .05 back in 09-10. Target 5 has been consistent and repeatable every year since.

You certainly found a good load there Swifty.

Shooting 5 x 5-shot groups is not a Ladder Test, but carry on . . .

Well seating depth and 3 shot groups isn’t a ladder either per se. I already knew max charge, what I wanted was to match the accuracy of 115 & 117’s. Just for conversation the 117 Sierra seats 3.150 the 115 BT groups at 3.16 the 110’s were 3.165.

Exactly. As long as you get consistent repeatable accuracy, you are good to go. Some bullets are far more sensitive to seating depth than others. Like Accubombs and Barnes mono's. I understand why a guy would want to find optimum seating depth with those pills. Other bullets are not as finicky. Generally those are the bullets I load. Non finicky bullets, temp stable powders, and proper primers make life much simpler. When working up a load, you should also be able to look at the pattern or group dispersion and know if the bullet needs to be seated deeper. As you shoot different charge weights, you should also see nodes. The groups tell you everything you need to know. You just need to know how to read it... I really don't like shooting 3 shot groups either, but if you shoot a 1 1/2" 3 shot group, there's no reason to shoot 2 more shots. When conserving components, I've worked up hunting loads with 3 shot groups. But you have to pay very close attention to the group dispersion and shape of the group. I for damn sure don't shoot 1 3 shot group and say it's golden. When I am working on precision target loads, I always shoot 5 shot groups and then confirm with 10 shots. Then its multiple 10 shot groups. I do the same thing for my varmint rifles and loads.

bsa- so what does the shape of a group tell you? What I noticed in my first initial test- which is what this was- was that longer depths in this case moved things to the right. I was pretty dang happy with all three groups and do plan to do more testing but like you mentioned, this limited availability of things takes a toll.

It sure does ken. Now, when you look at 3 shot groups, it is harder to know exactly what to do with seating depth. That's why a 5 shot group better in that regard. Its easier to read. You can see if you are double grouping better with 5 shots on paper. Generally when your rifle is double grouping, it means you need to seat the bullets deeper. So if you know you are .020" off the lands, seat them .040" and .060" off and see what the group looks like. A 10 shot group is even better, but it gets more costly and is not needed for general hunting loads. When I work up a load, I find nodes, like I said in the last post. Check these out, since you are working with 3 shot groups, I'll start there. When I see a group like you posted, I think of these in particular because you have 2 in one hole and the other one out by a ways. That tells me you are close to an accuracy node, but not quite there. That's where OCW comes into play big time:

First group:


Second group:


Third group:

You can see where the accuracy node is^^^^^

Good 3 shot groups should be triangular in shape, if not a single hole. Depending on the rifle's accuracy capabilities:

Then a 10 shot group should be round in shape. This one proves the load above to be a good one:


Another 3 shot group:

Then the same load, but proven with a 5 shot group (same rifle):


Recently I've been playing with my 7mm08 and 140gr TTSX. The rifle is new to me and I have not really wrung it out. This is also the first time playing with the Barnes TTSX in this rifle. As we all know, the Barnes bullets are sensitive to seating depth. I appreciate your thread, as it's got me to thinking more about seating depth. The only thing I found is it really likes .025" off the lands and magnum primers with Big Game powder. An odd thing I also found is it also acts very similarly when .100" off the lands and with the use of large rifle primers. I'm getting almost the exact same thing as far as speeds and group dispersion and group size. That's why I say, find an accuracy node. Find OCW, then you can play with different primers and seating depth. I'm not a believer in starting at book max and then playing with seating depth to find accuracy. As with any good load, it should always be "worked up" for safety and verify your accuracy nodes with multiple groups. With the recent load work on my 7mm08, I was able to accomplish this with a box of bullets. That's far more than I usually use, but because of this thread and bullet type, I was more inclined to play with seating depth. Had I just started as I usually do with the bullet .020" off the lands, I probably could have found a sub moa loading with less time, effort and components wasted. That's why I stress OCW. More times than not, that's all you need.

Great stuff BSA- thanks for taking the time. Now that I have the depth I plan on tinkering OCW a little.


Do you have any concerns about going below Min OAL listed in a manual? I noticed that the oal's I quoted for my 260Rem had two below what the book states it should be. The manual show 2.80 - 2.78 not exactly a lot of wiggle room.

Funny thing about seating depth, you are kinda fine tuning the load to your rifle. Change the charge which then changes velocity and pressure and boom, you are out of the node. Doing things backwards always has consequences. Some nodes aren’t very wide like +- 50 FPS, some are wider but that depends a lot on finicky your rifle is.
The other bad thing about seating depth is you need to find out how wide the depth node is ie exact, ~.002 or ~.005. since even bullets from the same lot can vary the ogive or you buy another lot and it just won’t shoot because the manufacturer made a change in shape or ogive distance that knocks you out of the node.
Charge first, then seating depth to fine tune.

How much below?

2.80 is SAMMI Max not minimum. Sierra shows test length with that bullet as 2.72.

Two of mine were below at 2.756 and 2.716 so.....largest gap was .064 below minimum.


Luckily I am settling on the load in the approved range but do want to know.

I would like to thank everyone for the great responses. I enjoyed getting back to this type of good chat without political angst etc...

I am being super finicky with my limited components. I was so glad to be pulling a trigger again and really happy that result were more than workable for my hunting needs. f I can find another pound of powder and the other bullets I really want to use I would be in heaven.

Remember those days....before Obama and hoarders? Thanks again guys. This was a nice respite with useful contributions.


Hey BSA- I have a 6mm Rem ( what is a WOA ? ) and want to go back to those same 85grain hpbts- right now I am relegated to the 100 prohunters. Curious- what was your load for those?

I listen to an F class shooter explain how he works up loads. When working up a new load he cares nothing about what they look like on paper. Once he find the most consistent speed that is the powder amount he uses.

Then he works back from .02 from lands or in case of some hunting rifles the max length of the magazine. He works back in .002 increments. According to this guy going greater than .002 may cause you to miss the sweet spot. He said usually you will find a sweet spot that is .004 in length. He uses the longest .002 spot to allow for barrel erosion.

It makes sense and I will be trying this method with the next couple of loads I work up.

Thanks,
Adams

I listened to an F class shooter explain how he works up loads. When working up a new load he cares nothing about what they look like on paper. Once he find the most consistent speed that is the powder amount he uses.

Then he works back from .02 from lands or in case of some hunting rifles the max length of the magazine. He works back in .002 increments. According to this guy going greater than .002 may cause you to miss the sweet spot. He said usually you will find a sweet spot that is .004 in length. He uses the longest .002 spot to allow for barrel erosion.

It makes sense and I will try using this method with the next couple of loads I work up.

I just went out shot a workup of .270 wsm 150 grain Partitions using Magpro. When I got to 68 grains my speeds were 2995, 2993, and 2992. From here I'm going to work backwards on seating depths in .002 increments looking to the sweet spot.



Thanks,
Adams

Well...finally got around to loading a few 270 with my new powder. I was down to my last two rounds loaded with IMR i4350 and one was snug in the chamber. I pulled the bullets and dumped the IMR as I am out of it. so why keep 2?

I will have you smacking your foreheads-....and I won't blame you. -but am cool with it. Just listening to myself for a change. The purists and self proclaimers will have a field day. So be it. Having fun here.

I ALWAYS just neck size with a Lee collet BUT because I found a separate group of clean looking 270 brass tucked away, not knowing where it came from, and because I had just had the one of my last two loaded rounds tight in the chamber, I decided to Full length size for my first test of H4350 in my 270. So, add one variable as compared to all other fire formed loads. Appalled yet?

I picked a modest 50 grain load- and by the way - depending on whose load data you read the reported fps on similar charge weights differed rather significantly, some reports showed very low velocity so I decided to try 50 instead of 49 grains. Lee shows 49 as minimal while Sierra shows 46.5. So 50 oughtta be good for those light hearted 140 Sierras on the typically closer shots.

Using my formula of testing at 0.04 increment depths I loaded 50 grain (easy to remember) three each at
3.340 ( accepted given length of factory ammo)
3.300 and
3.263 - the last one because I j got tired of slightly pulling then reseating trying to get exactly to 3.260 ....deal with it !! Ha .

Adams this is not discarding the 0.02 Idea. If I can manage something akin to a semi ragged hole with one of these three at 0.04 diff, call the good one , Load "X" , then next step might be for me to load two sets to compare. One at "X" +0.02 and one" X": -0.02. Make sense?

Taking bets on whether I can get a good group? And YES supposedly 3 doesn't make anything official (though I have never seen it NOT be repeatable).

If it holds true to form then I am guessing one of these will be at least fairly centered ( and before correcting me - no I don't really care because YES it is all about the tightness of the group) and am betting at least one will be close to a respectable group. .

Rifle iz CZ550 and it just plain shoots. Always gives me something old timers years back would call good-enough. Better than pie plate at a hundred! no matter what. ( and No...I do not consider 9 inch group acceptable - in case you missed that)

Just wanted to chime in again on this thread- and wish you and your families all the best this CHRISTMAS .


Ps- you will appreciate , years ago helped a friend's wife pick out a cheap rifle for her hubby- my bud. Stevens 200, Weaver K, shooting factory Corelokts.....dammit....tested zero after it sat in a closet for years and dang thing just rips single hole groups. Tell me life is fair? ha ha

Finally made it out to shoot and as expected - same results so I am considering this GOLDEN.

For the CZ mentioned in my last post, the longest COAL grouped nice and tightly in a triangle near the target center. The two shorter COAL's grouped higher with one stringing slightly vertical and the other horizontal.

On the 6mm the groups were very similar and again the longest coal, near factory length, was great.

So 2 of 3 rifles liked the longer depths- with these light loads.

The 3rd rifle, my 260 liked the middle COA length best.

The best load for all rifles were at or under 1 inch.

So now I guess I can plus and minus the charge by .5 grain to see if it gets even better. Whether or not it does - I am pretty well good to go.

I N T E R E S T I N G


Something struck me this morning .....so I went and checked.

I verified that all three of my best loads were created using the factory standard COAL.

Just checked it this morning. Within 1/1000th

This after going up and down looking.

Makes me wonder what the hell I been doing all this time.

How does the case head to bullet ogive distance compare?

Mathman - get where you are coming from . I can measure but I am not changing bullets so not sure how much it matters. I might have some Hornady around and could compare to previous loads. Have to look. I have to re-measure magazine lengths too it would seem. Two of three don't give me much room after factory spec. I started out thinking not all of my rifles liked the longer lengths best but it is beginning to appear otherwise.

If we are talking about tuning seating depth in increments of only a few thousandths at a time the differences in bullet tips in the same box, especially lead tips, can throw a wrench into the works. Never mind the difference in tips from one box to the next, or one production lot to the next.

My increments were in 4/100's. I might go up or down another 1 to 2 / 100's......from here. I am at magazine length mercy.