Extremely poor results... Lapua, AMAX, CFE & XBR

[1911man]

I'm going to load up some 1.785", 1.745", and 1.705" bullets and single load them to see how they perform.

If those longer loads shoot great, I'll be selling this Radical barrel and buying a 24" Satern barrel. Component cost is too high to mess around forever with a barrel that has showed zero promise!

This is a barrel I have had my eyes on for some time. I believe all of Raniers ultra match barrels have a sub MOA guarantee: https://www.rainierarms.com/rainier-...ndel-barrel-22

[tommag]

I have the radical 24" upper and mine prefers the 85 sierras and the 100 gr amax. Using the stony point guage, the 100 a max has a jump of .05. I just measured the Sierra 100 gr flat base hp and it will touch the lands at 2.223. I know it doesn't have a high bc, but I think it'll be a good choice for 300 yds or less.

[BarrelNut]

Tommag- Did you try the 123 AMAX's? What magazine are you using and what is the OAL on the 100gr Amax load?

[tommag]

I've only shot a half box of 123 amax and the accuracy wasn't great, about 1.25"@100 yds.
I'm loading the 100 amax with an oal of 2.25", giving me a jump of .05". This was in lapua brass, cci 450, and 30.2 grs of 8208. This load have me a .4 group the first time, and similar results the next trip. I did get a couple flyers out of a group of ten, but I wasn't shooting well that day. I'm going to try that load again tomorrow.
I'm using asc magazines.

The 30.2 gr 8208 load was with 100 gr amax.

[bwaites]

I've only shot a half box of 123 amax and the accuracy wasn't great, about 1.25"@100 yds.
I'm loading the 100 amax with an oal of 2.25", giving me a jump of .055". This was in lapua brass, cci 450, and 30.2 grs of 8208. This load have me a .4 group the first time, and similar results the next trip. I did get a couple flyers out of a group of ten, but I wasn't shooting well that day. I'm going to try that load again tomorrow.
I'm using asc magazines.

30.2 of 8208? That's a STIFF load, almost 2 grains beyond the max loads I've seen recommended. Is that number right?

[tommag]

30.2 of 8208? That's a STIFF load, almost 2 grains beyond the max loads I've seen recommended. Is that number right?

The 30.2 gr load is with the 100 gr. Amax, not the 123 gr a max. From the grendel book, BWild97 shows going up to 31 grs.. Groups started to open up for me above 30.2 grs.

[BarrelNut]

That's great to hear tommag. Looking forward to see how your further tests turn out.

[tommag]

After learning that I can seat the Sierra 100 gr hp into the lands, I loaded 25 of them with #41 primers and wcc 844 with a .003 jump. I started at 29 grs and went up to 31 grs in .5 gr increments. I'm optimistic, but I've been disappointed before.
In my chamber, I find almost nothing that will seat close to the lands with a reasonable amount of bullet in the neck.

[tommag]

The 100 amax didn't do well today, 15 rounds in 1.4". I switched primers, from cci 450 to #41s. I dont think that would account for that big a change.
Two different powder charge weights with the 100 Sierra fbhp grouped at .78 and .82. That was the best I could do today.

[JASmith]

The 100 amax didn't do well today, 15 rounds in 1.4". I switched primers, from cci 450 to #41s. I dont think that would account for that big a change.
Two different powder charge weights with the 100 Sierra fbhp grouped at .78 and .82. That was the best I could do today.

FIFTEEN rounds in 1.4" is doing very well thank you!

That should work out to sub moa for a large fraction of one's 5-shot groups.

If, on the other hand, the "1" in front of the "5" is a typo, then I can understand your frustration...

[tommag]

FIFTEEN rounds in 1.4" is doing very well thank you!

That should work out to sub moa for a large fraction of one's 5-shot groups.

If, on the other hand, the "1" in front of the "5" is a typo, then I can understand your frustration...

No, not a typo. Measuring with calipers, it's more like 1.6" most are clustered tighter than that, but 4 shots are out a bit. I've got my brass in the media, next time going back to 450's and see if that's the problem.

[JASmith]

There is a neat statistical analysis at http://the-long-family.com/group_size_analysis.htm.

The table gives group size correction factors. The factor for 15 shots is 0.590 so your 1.6" group suggests that your dispersion is more more like 0.94 inches.

To get an idea of what this means, a rifle and ammo combo producing a series of five shot groups that average 1" center to center will have a dispersion of 0.876 inches.

Have you considered using a different aimpoint for each five shot group?

[tommag]

I'm not educated enough to wrap my head around the statistical analysis stuff. Normally, I shoot five shot groups, but had an almost full magazine and there was only one point on the target left. This was my last shooting for the day and I decided to bang them off rapidly to heat the bbl up a bit for cleaning.
I cleaned my brass today, and loaded 20 with cci 450s and the 30.2 8208 load to see if the primer makes that big a difference. In loading them, I introduced another variable, seating the bullets as far out as I could and still fit the magazine. I'm thinking this will improve things, with only a .005 jump.
I was pleasantly surprised by the cheap PRVI 120 gr bullets today. Under an inch for five shots is way better than I expected from them. I'll have to try them with a bit of tweaking.

[LRRPF52]

I just saw Radical Firearms pop up again for barrels turning out of the extensions while being fired, not from muzzle device removal.

They said there was a vendor they were using at one time that had problems with the nitriding of barrels, so I hope that doesn't apply to these for those who got them.

[tommag]

Mine is a stainless barrel, so I don't think I have that problem. They are cheap and I probably got what I paid for. Being new to the ar world, I don't have a baseline to compare to, but it's more accurate than my old mini 14. Not much of a comparison, but I've always had bolts and pumps.