Muzzle Velocity (???)

[Doublecluck]

I had good results with imr 4451 and 140 ab’s. 2850 out of a 24” tube with 45grs. But I wouldn’t give up on that varget until you run it to max. As stated groups usually open and close thru the safe powder range and it’s very possible your groups could get smaller again toward max load.

 

[Sask hunter]

I had good luck with 139 hornady interloks and a max load of IMR 4350. might be faster powders for it but I always had lots of it on hand. It has taken two moose and a couple bears as well as s bunch of deer

 

[Millsworks]

Shouldn't have any trouble getting an accurate load at 2,800+ fps or so.
They don't have to be super fast, but the 7mm-08 has certainly got potential left at a mere 2,400.
I would look at a better powder or keep loading up until pressure sighns show up and then back off a few grains. Then play with the seating depth for accuracy.
I have always believed getting accuracy and performance from a rifle is the main reason to reload.

 

[huronmtns]

Since Brian will probably be looking at another powder to look at some velocity gains I thought I would post some velocity numbers that I am seeing while developing loads for my new 7mm 08. Keep in mind these velocities are on a 20.5 inch barrel length. Here are four different powders all working with 140 gr Accubonds:

Reloader 15 41.5 gr Max charge, 2664 FPS
Varget 42.0 gr Max charge, 2742 FPS
H 4350 48.0 gr Max charge. 2757 FPS
Ramshot Big Game 47.5 gr Max charge 2859 FPS

Big Game will give you a significant jump in velocity but in my experience with it comes with the price of a large extreme spread. I'm still working on ruling out some variables that might be causing it though.

These velocities were taken during temperature around 20 degrees F. I would expect these velocities to increase a bit in warmer temperatures.

Millsworks, I suspect you meant to back off a few tenths of a grain not full grains in you post above. Four full grains is a large jump in a 7mm 08 charge weight.

 

[N2TRKYS]

Since Brian will probably be looking at another powder to look at some velocity gains I thought I would post some velocity numbers that I am seeing while developing loads for my new 7mm 08. Keep in mind these velocities are on a 20.5 inch barrel length. Here are four different powders all working with 140 gr Accubonds:

Reloader 15 41.5 gr Max charge, 2664 FPS
Varget 42.0 gr Max charge, 2742 FPS
H 4350 48.0 gr Max charge. 2757 FPS
Ramshot Big Game 47.5 gr Max charge 2859 FPS

Big Game will give you a significant jump in velocity but in my experience with it comes with the price of a large extreme spread. I'm still working on ruling out some variables that might be causing it though.

These velocities were taken during temperature around 20 degrees F. I would expect these velocities to increase a bit in warmer temperatures.

Millsworks, I suspect you meant to back off a few tenths of a grain not full grains in you post above. Four full grains is a large jump in a 7mm 08 charge weight.

After hearing about how good Big Game powder was in the 7-08, I decided to pick some up. It was very accurate, but about as fast as Varget for me. I'll probably try to sell what I have left. RL16 uncorked the torque for me in my rifle. Funny how it can be so different in different rifles.

 

[huronmtns]

If I can find some RL 16 in my travels this spring I'm going to give that a try in my loading too.

 

[JLS]

Yep...me too.

Me and three. Shoot up to max. It may surprise you.

 

[huronmtns]

Yep...me too.

X 4 I've seen it with a number of different powders and gun combinations too.

 

[TimeOnTarget]

X 4 I've seen it with a number of different powders and gun combinations too.

x5. You generally will get accuracy nodes throughout different charge weights. Just hope you can be back on that accuracy node before pressure shows up.

 

[std7mag]

I tried RL16. Wasn't happy with it.
Ramshot Big Game is made of unobtanium in central PA.

I'm using RL17 and Alliant Power Pro 2000.

Superior velocity with 17.
Lowest ES, DS with PP2000.

 

[1_pointer]

Seating depth is not something I've played with, would you suggest a little deeper or a little longer?

Also, I have a pound of H4350 on my shelf; I'm probably going to try some loads with that.

This question is why I start my loads like Buzz does, just off the lands or at max mag length. That way there's only one way to go with seating depth. Like others have said, I wouldn't start changing anything until you finish the test rounds you have.

 

[cahunter805]

Brian

My guess is the 41 or 41.5 load the accuracy will start tightening up again. I'd load up to 43gr and see how it shoots. Watch for pressure signs and report back. After you have tested higher charges then we can further test seating depth or another powder.

 

[JLS]

This question is why I start my loads like Buzz does, just off the lands or at max mag length. That way there's only one way to go with seating depth. Like others have said, I wouldn't start changing anything until you finish the test rounds you have.

Yep

 

[Tjay]

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They also have 1 pounder and also alliant 16 1 and 8 pounders.

 

[haiku_rodney]

My hunting load for my 7-08 is the maximum from loadbooks. I shoot a 140 Sierra BTSP with 47.2 gr of IMR4350. I get about a 2-3" group at 200 yds. Velocity is supposed to be around 2900 fps. I do not have a chronograph so I couldn't verify the number. What I can tell you is I have killed goats, pigs, axis deer and feral cattle with it. They don't always drop on the spot but I usually find them within 50 yds. Accuracy is nice, but as one member said if you can hit a paper plate you can hit the vitals. I think you have to balance accuracy with velocity/bullet energy.

I shoot Sierra's in my 7-08, however, I think the Nosler Accubond is a great bullet. I shoot it in my 30-06 AI for feral cattle. Very effective bullet on them, drops them in their tracks. Killed a cow at 640 yards with that bullet.

 

[Brian in Montana]

My plan at this point is to finish shooting my test loads. Hopefully the groups will close back up. Once I'm through those I figure I'll take the most accurate load and play with seating depth. It makes sense to me to deal with only one variable at a time.

I'm also going put together some test loads using H4350. I'm anticipating higher velocities with that. Lots of testing to do. But that's the fun of it.

 

[Brian in Montana]

OK, I spent some time at the range today and finally finished up those Varget loads, so I thought I'd report.

As some of yous predicted, the accuracy came back with higher charges. Shooting 5 shot groups I found a good accuracy node at 41.5grns - 4 shots were within about .85", 3 of them touching, with the 5th shot being an annoying outlier I'm inclined to write off as user error. 42grns wasn't bad either. 42.5grns was as high as I went, but was beginning to open up again.

It's so weird how this works. It's pretty fascinating, really. 38grns of Varget going up to 42.5grns: I started on an accuracy node, saw it open up, close again, then start to open up again.

Anyway, I also burned a bunch of H4350 pushing 140grn Nosler AB's - there was nothing in that batch I intend to reproduce. I came out with some pretty high muzzle velocities, but none of my groups were what I'd call "accurate". Didn't do better than about 1.75". I can do better than that with factory ammo.

At this point, since bear season is fast approaching, I'm going to load up the 41.5grn Varget load, chrono it (I didn't get my chrono out today as it was very sunny and the ground is snow covered), and maybe mess with going about .2grn higher and lower - just to see. Anyway, I think maybe I've found something to hunt with.

Comments and advice welcome.