Home Forums Reloading Big Game Rifles New to me 7mm-08

Hodgdon's online data has 7mm08 in the handgun section. There you can see what they got with a 15" barrel.

Savage Striker 14" barrel I've run both R15 and Varget through it with equally good results my load right now is
44gr R15 with 120gr BT...Varget was 44-45 gr also same bullet...Those are the only powders I've used in the gun as they work so well there was no need to try any others

I actually have looked at it. They only list Hodgdon powders interestingly enough.

Also, I run into almost the same issue as looking at data for the longer barrel stuff. The closest I can find is an old Hornady manual I have in where they used a model 7 with 18.5" barrel for their tests. However, they only have the old'n powders listed. It is interesting to see that their data max's out at 2600fps for the 139gr bullet.

Did you try any 139/140 grain bullets?

140 gr BT also shot well thats what I killed the antelope with

Just for example, their 47gr H4350 load I am getting 100fps more than they are.

Sorry for the long winded post. I got out and shot again yesterday. Moved the chrony out to 15'. I did not get to shoot much, and that might be a good thing to help me sit back and think about things. Hopefully it might add more information for others to see something.

I had loaded up 4 rounds the night before of what seemed to be the best shooting 4451 load. The first three shots were right there grouping 1/2", and then the next shot was way off in left field. It was not a pulled shot. I just don't know what to think. That load averages 2450fps. Which is very interesting because of the POI on the target. In the picture it is the bottom left.

Then I decided to try the H414 again, and get some velocity readings from it. I first tried the 46 grain load. Top left in picture. It grouped in ok I guess. Maybe I am being picky? I did not get an exact measurement, but its right around .8". Average velocity is 2535fps.

Then I decided to up it, and see if I pick up velocity and see how the group reacts. I shot 46.3(not 46.5 as the picture indicates). Lower right target. Definite POI shift and one of those dang fliers. Interestingly enough though, the average velocity of those were 2525fps. I would say this is a case of false readings, and it may be to an extent, but I did not notice ANY speed gain over the 46 grain load.

Here are the readings of the two.

46gr
2531
2547
2528

46.3gr
2527
2545
2505

So no major velocity differences, actually pretty close, and the POI shifted just about 1" to the left. Very interesting to me.

Last but not least, I said I would do it so I did. I tried a load of Varget. I chose to use 42 grains to start. I wish I could have shot more just to see, but I am not sure if I might not get frustrated by it. Reason being, the 42 grain load was the smallest in the bunch coming in at ~1/2". Top right target. However if you notice the POI it is low(compared to factory loads) and it only averaged 2413fps.

I had to quit at that point, it was getting dark anyways. I'll try some higher loads, who knows it may work, but if its like anything else I am thinking the groups will start to open up. Maybe I will prove myself wrong. I'm about out of bullets so I am going to have to decide what I want to pursue next if that does not work. What I did start to notice is that this Sierra bullet seems to want to run with a mild load. In fact, each powder I've tried - H414, H4895, IMR4451, H4350, and Varget - all have produced good groups with midway loading's(between start and max using Hodgdon data).

I don't see this as a complete surprise. I have for the most part seen most of the best groups, from various guns/cartridges, come from mid to upper mid loads. Never from minimum or from top end. I'm starting to believe that I am going to have to settle for what it is. I choose to go the shorter barrel route and this is part of the outcome from it. If only I had access to the powder that Hornady uses....

I know that 2500fps is not horrible, and really for the most part it will do just fine. But I bought the gun specifically to use for deer and the occasional elk hunt. I knew for deer it would be a great gun, and for elk it would be OK as long as I limited my shot distance. I had hoped to have that distance be 300 yards, but when doing calculations I really feel I need to be in the 2550fps range at the muzzle. Of course, those numbers I recorded yesterday were at 15' from the muzzle, so MAYBE they could have 20-25fps added to them.

I think I am going to get some of the Hornady's to start work with. Maybe my gun just does not like Sierra. I say that tongue and cheek because other than a few of those groups, years ago I would have been ecstatic to have a gun shoot like that and I would not think twice about hunting with it. Maybe its a bit of OCD or something. I just feel I can do better with it.

Thoughts?

Dunno how much experience you have so forgive me if I come across wrong. But I stopped with the 0.3 level of measuring after seeing it mattered very little and I ended up chasing fliers and other minutae.

In a case that size I start at whole grains and once I see a promising pattern develop I go up or down a half grain, or work on overall length. Not trying to shoot flies, and I end up with sub moa this way anyway.

Just for reference, the circles on the target are little less than 3/4" apart.

No worries, I am not easily offended. I don't have as much as some, but I've been at it for a while. 5 years or so maybe? I do not pretend to know it all, only what I have learned, which is why I am always open for other experience. I learned on my own, not taught by anyone, just always trying different things to see what works. What I have learned is that hand loading has a WIDE range of traditions, habits, and opinions. Which I understand completely.

My personal experience is that I have seen .3 difference matter when I get around a load that works good. My standard is to load in .5 grain increments and then fine tune with .3.

I don't do the 1 grain steps in this size cartridge just because with some powders that would mean only two loads before I am either below start or over max.

I did have one thought cross my mind. Is it possible a heavier bullet would be more efficient in this scenario?

My thoughts on it are it would be harder to push down the barrel, so that means slower, but at the same time giving the powder more "time" to work on it.

I will state that I am not a believer in faster powder/short barrel theory(to a point). I do firmly believe that powder burns in the first 16 or so inches of a barrel.

Going back over my notes and pictures, I did not fully explore H4895 like I should have. I was using the Hodgdon 140 grain data before I had found out that I can use the 139 grain data.

Whats significant about that is the 140 grain data tops out just over the start data for the 139. So I could have gone a lot further in my tests, plus the top load(40.5) did show some promise.

I found that the .3 loads might look good but were more a statistical anomaly. Shoot thst load for a group 5 more times and see if it still holds up. As you posted, adding .3 resulted in slower speeds and not even one pct difference in speeds, kind of erratic.

My thought was actually that the 46 grain load had reached the maximum velocity/pressure that was accurate. That was the purpose of going over .3, just to see how much it effected things, and from what I saw it did.

I'll agree, for most work .3gr is not going to amount to much. But in reality it does effect things. Maybe I am trying to squeeze the loads too much in an effort to get the best one, but I'm one of those guys that if I think about something without doing it then it haunts me until I do it.

I have worked up loads before that shot great, then changed the seating depth or something else only to find out the load did not shoot like it did before. Changing it just a few tenths of a grain brought things back together.

Maybe its dumb luck, or just pure happenstance, but I still stick with it. Just not for first time group testing. That I only do in .5 increments.

Every gun is an individual. Whatever works for you

Well I think I have figured it out. I think its me not being consistent while shooting. I thought that if I put my gun on the led sled it would take me out of the equation. But after thinking about it, unless I put the rest in the same position, and the gun in the same position, even the little bit of cheek weld and torque on the grip I have can effect the way the gun behaves shot to shot.

I guess I just assumed it would be so little of an effect that I did not have to be consistent with those things. I just did not take into effect that as soon as the trigger is pulled there are reactions going on and that its not all happening after the bullet leaves the barrel.

Makes complete sense why smaller caliber, lighter recoiling, rounds are more consistent. Lesson learned.

I have some Hornady 139grain flat bases coming next week so hopefully I can put all my lessons to good use.

I thought about it, and decided to take your advice. Got home and loaded up 3 with 47 grains of H414 because I wanted to see what the velocity increase might be and just what it might do on paper. Shot those three and they printed right at 1/2". Got excited, loaded 2 more to make a 5 shot group, and the fourth printed in the middle of the others, but the 5th opened it up to just over 1". I am not complaining needless to say.

Loaded up 5 more and shot at 200 yards. Again, just over 2" with a flier opening it up to over 2.5"

Nice thing about it is they are hitting same POI as the hornady factory loads, and I am measuring just over 2600 fps average.

Too bad it took me the whole box of bullets to finally find this. Oh well, lesson learned. I will have to say that half my battle was the darn rest I think. Note to those using them, you still have to have consistent hold on the rifle and consistently put it in the rest the same way. Have to wonder what the other loads might have been like now.

I think that some fine tuning of the OAL will bring me even tighter. But I have reached my goal. Now I get to start all over with the other bullets next week.....

I'll stick with H414 though. I was not seeing any muzzle blast like I was before with other powders. I rarely do any shooting in hot weather so I am not concerned with temp sensitivity. Some more practice and I'll be good to go with this gun.

Have to stretch it out further now and see what it can do. I wish I had thought to contact Hodgdon in the beginning to see what data I should use. I was originally going off their 140 grain data for H414 which max is way under 47 grains. No pressure signs at all with my load.

I'll keep things updated when I develop the load with the new bullets.

Hard to know on a 5 shot group if you were losing concentration or if the load is inconsistent...I struggle with that too. Another thing I do is test loads at 50 yards to try to take wind and my skills out of the equation. Then move to 100 to verify once you find a good one.

Do you find 50 yards is far enough? I would think at that distance, unless something is way off, most loads are going to be tight.

I'm not opposed to it, just never considered it.

If wind isn't an issue I prefer 200 yards.