Which group would you pursue?

[LocoGringo]

So I think from what I've read that vertical stringing indicates velocity changes within the load and that clustering is better. However, the measurements of the top group are .886" 6-shot group and .524" for a 5-shot group. The bottom target is 1.133" 6-shot group with the "flier" and .631" 5-shot group. This is a .308 AR shot by my buddy for whom I'm trying to get some good hunting ammo loaded.

Which group would you pursue? They are within .2 of a grain of each other...the top target is 42.7 grains of H4895 the bottom is 42.5 grains. I know it's a small sample to decide, but humor me...

 

[Ranger99]

So how far away was this
shot at ? 100 yards ?

 

[LocoGringo]

So how far away was this
shot at ? 100 yards ?

Yes, 100 yards.

 

[Ranger99]

Just me- I'd shoot both again
to eliminate any variables from
the first session
Make sure the gun is consistent
I'd probably diddle with the lower
batch if the flyers disappeared
My limited experience with AR's
wasn't as productive for me as
with "regular " rifles

 

[entropy]

The bottom group, assuming same zero, and the flier being trigger actuator malfunction. Matter of fact, I'd try 42.3 and 42.2, they may be more accurate yet.

 

[LocoGringo]

The bottom group, assuming same zero, and the flier being trigger actuator malfunction. Matter of fact, I'd try 42.3 and 42.2, they may be more accurate yet.

The loads ranged from the lowest being 41.9 and the highest being 43.3 in .2 grain increments. The two groups I posted showed the most promise.

So which group would you pursue?

 

[Walkalong]

I would shoot more groups

 

[Larry in wyoming]

Conventional wisdom says vertical stringing equals add more powder. Round groups are desirable. Shoot em again till we're sure that's what the load is really doing and get back to us
I'd chase the bottom load.

 

[AJC1]

A flier needs to be investigated as neck tension or shooter. Does the brass or shooter repeat. .5s are more than satisfactory for animals

 

[kmw1954]

Honestly, I don't see much difference between the two targets. Some of each could easily be shooter influence. Shoot them both again see if it repeats. Better yet shoot them round robin at separate targets points on the same stand. Still the same? Move out to 200yards and shoot again.

Sorry but I don't place a lot of faith in a one round test target, whether it be a 3 shot group or a ten shot group. When I find a load that shows promise I shoot it, load it again and repeat the process. Does it still hold up a few days later?

 

[lordpaxman]

So I think from what I've read that vertical stringing indicates velocity changes within the load and that clustering is better.

That’s a great reason to have chrono data when doing a work up. I’m skeptical about vertical stringing at 100 yards without serious delta Vs.
If I had to choose between those two, I’d flip a coin. Or, the 42.5 saves you .2 grains of powder every trigger pull. After 212 rounds, you‘d shoot one extra.

 

[Buzznrose]

View attachment 1163071

So I think from what I've read that vertical stringing indicates velocity changes within the load and that clustering is better. However, the measurements of the top group are .886" 6-shot group and .524" for a 5-shot group. The bottom target is 1.133" 6-shot group with the "flier" and .631" 5-shot group. This is a .308 AR shot by my buddy for whom I'm trying to get some good hunting ammo loaded.

Which group would you pursue? They are within .2 of a grain of each other...the top target is 42.7 grains of H4895 the bottom is 42.5 grains. I know it's a small sample to decide, but humor me...

If these were 100 yard groups from an AR10, what more are you asking for?

 

[243winxb]

They are within .2 of a grain of each other

I dont see that small of a difference in a powder charge making much change @ 100 yards.

Top group- load 20 rounds & fire 4 groups of 5 shots each for an average. If under 1" you have a load. This also tests the ability of the shooter.

Dont fire using a bipod. Use sand bags, front and rear. Its ok to hold forearm down, while its resting on the bag. Dont want it jumping up during recoil. Straight back is best. Helps reduce vertical.

 

[243winxb]

Avoid his.

 

[Random 8]

Shoot 10 more of each if you like.

Otherwise load the heavier charge and kill deer. It is plenty consistent for the purpose. If your buddy wants a 400 + yard load for that platform, slap some sense into him.

 

[LocoGringo]

So here's why I'm trying to keep the round count low. I'm doing this as a "thank you" for him helping me with some cerakoting I had done to some AR parts. I figure he saved me about $200 on a very nice job. I don't want to sink $400 worth of ammo components and time into this. I did 50 test rounds and will do 50 finished rounds for him. I know a MUCH larger sample size would be MUCH better, but that also increases the costs of the favor I'm doing. Don't want to go there.

These are deer hunting rounds for East Tennessee. A long shot might be 200 yards. Mainly I'm focusing on the vertical stringing that appears in the upper target and, if I'm correct, vertical stringing indicates velocity differences which is bad...I think, right? The clustered target, while a larger group, would indicate a little more consistency, right?

 

[Larry in wyoming]

Stop right where you're at. Load the bottom group. Tell him it's M O.A and everyone is happy. No deer at 200yds is ever going to know the difference.

 

[Larry in wyoming]

By the way, which AR10 is it?

 

[kmw1954]

Mainly I'm focusing on the vertical stringing that appears in the upper target and, if I'm correct, vertical stringing indicates velocity differences which is bad...I think, right? The clustered target, while a larger group, would indicate a little more consistency, right?

If you want to call that vertical stringing then go ahead. My eyes tell me the overall group shape is the same for both. including the lone shot off center. As I see it both of those groups are taller than they are wider. I would not get excited by that small of a dispersion. Especially for a hunting round.

 

[IALoder]

Honestly, I don't see much difference between the two targets. Some of each could easily be shooter influence. Shoot them both again see if it repeats. Better yet shoot them round robin at separate targets points on the same stand. Still the same? Move out to 200yards and shoot again.

Sorry but I don't place a lot of faith in a one round test target, whether it be a 3 shot group or a ten shot group. When I find a load that shows promise I shoot it, load it again and repeat the process. Does it still hold up a few days later?

Beat me to it! Either one is a winner if it repeats and stays under 1moa @200. REAL darn good for an AR10!

 

[LocoGringo]

By the way, which AR10 is it?

I don't know. It's his rifle and he did the shooting/testing. I told him how to do it and he gave me the labeled targets after he was done. He said he was actually happy with ALL of the targets. There were no malfunctions but the higher charged loads were obviously more powerful. I didn't push pressures though and stayed away from the extremes of low and high in the books.

The load is Speer Boattail big game 165 with (it looks like the charge will be) 42.5 grains of H4895. It looks like his rifle likes that bullet and powder combo pretty well.

I just want to get the best performance for him that I can without sinking a lot of money into it.

 

[Larry in wyoming]

Load him up a hundred and call it good.

 

[stigfender]

If you're buddy is going for squirrels at 200 meters, keep trying But for deer inside 2-300 meters your already there!

 

[Highland Lofts]

I'd go with the lower group.

 

[ArchAngelCD]

I agree, shoot more groups but since you want to limit components just go with either. Let the shooter pick.

IMO if he can't hit the vitals with either load he might need to practice more or get a different gun. Both look fine but the bottom might be better.
Load um up and send him hunting. Day over...