Testing setback or creep in various bullet weights through my 6mm ARC and how to prevent it from happening. Sometimes it's all the little things that add up to make better accuracy.
Good comparo. I'm running 87gr V MAX and after watching the videos -probably the same ones you watched- I measured and didn't see any jump either. Not saying it doesn't happen. I'm using resized Starline brass. Also I worked on my feed ramps and I'm using a + strength buffer spring. The 87gr V MAX in the ARC is a fantastic combination. My rifle prints them at .5 - .75 MOA all day, and so far I have reached out to 786 yards on targets and about 450 on prairie dogs.
Great info, I have working on what seems to be a problem with the 6, I noticed that there is quite a difference in the factory ammo length, After realizing the extent of the factory variance I trimmed the brass and installed an adjustable gas block. Well that started a whole different set of issues, it however seems to be the avenue to go, with the block mostly closed I was able to print some less that 1/2 moa groups without the usual fliers but I had an undesirable ding in the case neck, so from there I opened up the gas port 1 rev which resolved the case damage but printed a horizontal group of 13 rounds in 2" so back to the drawing board. Quite a finicy AR round!
The AR platform can definitely be finicky! My friend has a 308 which the most accurate handload we developed virtually turns it into a single shot. Bolt actions are so much easier 🤣
If you are getting two dings on the side of your brass, it is your feedramps. Looks like barrel manufacturers are using 5.56 barrel extensions which are too narrow for the fat cases of Grendels and ARCs. I ended up smoothing out the hump between the two ramps quite a bit to solve that problem.
I had this issue then started using the short action custom bushing die to get my neck tension in check. Was using Hornady full length sizing die before. Also using alpha munitions brass and not Hornady brass anymore.
If 1 or 2 thou is causing a problem your at a bad seating node or just seat the bullets in a couple thou deeper. I have not found that my bullets move when cycling them. Best powders I've found are Leverevolution for speed and Varget for best accuracy. Thanks for the video!
If you have single digit SDs and you’re not grouping it’s a barrel harmonics issue… Save the barrel and play with seating depth or just throw a barrel tuner on it. Also check your barrel twist rate and confirm it will stabilize the bullet you’re trying to run. That could also be the issue. Lots of times barrel twist aren’t as advertised and when you check it you’d might find that it’s off.
Unfortunately I've spent almost 4 months trying 5 projectiles with 4 types of powder including 3 seating depth tests to no prevail. A tuner has crossed my mind just to seeing it could shrink groups a little.
@@thelonggunner762 The tuner will… but it’s all in what the barrel is really worth to you. I didn’t stop and think about that in my prior statement. The same thing happened to me with a Ballistic Advantage barrel and at the end of the day I pulled the barrel and threw on a Proof. I knew that’s what I should have done from the start. At the end of the day I didn’t feel that barrel was worth or justified the cost of adding a tuner are 200+ dollars. In general a tuner will tighten any guns groups overall .
By the way great job on the video. Everyone shooting heavy bullets in a 6 ARC gas gun is going to contend with bullet creep or set back if they are serious about trying to shoot the smallest group possible. One thing I’ve come across with using a crimp is brass length has to be spot on and everything has to be concentric to get an even crimp. If not you’re just introducing uneven neck tention on the bullet.
I reload for 6arc too my first 300 rounds were 200 rounds of Hornady 108ELD-M, 100 rounds Hornady Black 105 bthp the 108's were all 2.690 @ogive w/ #24 comparator the 105 Black were 2.695@ ogive I reseated them to 2.690@ ogive went from 1" to .33" @ 100 yds the 108's shot great as is. Now when I reload I seat all my bullets @2.690@ ogive 87gr-108's
As a fellow handloader, I enjoyed your video. I did notice that you used the hornady comparator gauge 2-22 to measure your comp. Shouldn't you be using the 2-243 gauge?
Glad you caught that, I was looking at it too. But I think for the intended purpose it provided a reference point as long as measurements were taken from start to finish with the 2-22.
@dpwild328 unfortunately it turns it into a 2 step process. I run them through the sizing die with the expander ball taken out the run them through the Wilson mandrel die.
@thelonggunner762 I have almost the same build - Aero Precision with Proof 18" barrel. I'm working my way through the cycling problems. It will do everything but lock back on empty. Probably going to add the reduced power buffer spring that you did. Is yours still running good? How is the accuracy?
