129 Absolute Hammers in 6.5 SAUM

[Idaho Hunter1]

Trying to figure this one out, 6.5SAUM with 1/7.5tw and the 129 Absolute Hammers are not grouping.

The rifle is shooting Barnes 127LRX and Hornady 143 ELD-X into sub-half and usually quarter minute groups with H1000 or RL26, ADG brass, CCI or FGMM magnum, COAL 2.845". Neck tension is .0035 but have tried .002-.004 and it worked fine. Loves them all.

I've tried these above combinations of powders, primers, and also RL23 and am getting 4" groups at 100yds. Worked up to pressure after consulting with Butter Bean and others and have it humming along between 3150-3425fps and still groups don't tighten up. I've cleaned the barrel, nothing. Changed optics, nothing. Run COAL from 2.790-2.850 and the same thing. I can't reduce the jump anymore due to SA mag limits (no Wyatts). Neck tension has been varied between .002-.004

So has anyone else had this issue? Any ideas?

Im about ready to hang them up.

 

[ButterBean]

Trying to figure this one out, 6.5SAUM with 1/7.5tw and the 129 Absolute Hammers are not grouping.

The rifle is shooting Barnes 127LRX and Hornady 143 ELD-X into sub-half and usually quarter minute groups with H1000 or RL26, ADG brass, CCI or FGMM magnum, COAL 2.845". Neck tension is .0035 but have tried .002-.004 and it worked fine. Loves them all.

I've tried these above combinations of powders, primers, and also RL23 and am getting 4" groups at 100yds. Worked up to pressure after consulting with Butter Bean and others and have it humming along between 3150-3425fps and still groups don't tighten up. I've cleaned the barrel, nothing. Changed optics, nothing. Run COAL from 2.790-2.850 and the same thing. I can't reduce the jump anymore due to SA mag limits (no Wyatts). Neck tension has been varied between .002-.004

So has anyone else had this issue? Any ideas?

Im about ready to hang them up.

Are you crimping and what is the case fill ?

 

[Idaho Hunter1]

Not crimping and case fill is 95%+. I get nice velocity plateaus that are about a grain wide but still not grouping.

 

[-WARDOG-]

I would try single loading to play with the jump to the lands. If it starts to group then you know trying to limit the COAL to fit in the mag is the problem.

 

[Idaho Hunter1]

Good idea. I had stayed away from that because it is for hunting and while I'd like to think I'll only need 1 shot, history has proven that not always the case.

 

[Wedgy]

Measure your barrel twist to see if it is indeed a 7.5 twist, push a patch or brush thru and measure how far you push to make one complete revolution of the rod. Many barrels and not correctly labeled.

 

[Idaho Hunter1]

Measure your barrel twist to see if it is indeed a 7.5 twist, push a patch or brush thru and measure how far you push to make one complete revolution of the rod. Many barrels and not correctly labeled.

It's verified at 1/7.5. Thanks

 

[Korhil78]

It may be superstition on my part but if I am changing bullets, I clean the barrel down to bare metal and then shoot 2 or three fouling shots with the lightest load of whatever I am testing.

 

[lancetkenyon]

Talking with Steve, the Absolutes like faster burning powders, not normally associated with the cartridge size. They need to pressure up faster since the ogive and "bearing surface" are actually undersized,and do not contact the lands. Only the drive bands do.

I am running the 129 AH in my two 6.5SSs (20" & 26", both 1:7.5") over H4350. Amazing results with H4350. Great accuracy, good velocities too. I would try a faster powder.

 

[ButterBean]

It may be superstition on my part but if I am changing bullets, I clean the barrel down to bare metal and then shoot 2 or three fouling shots with the lightest load of whatever I am testing.

Always a good practice

 

[ButterBean]

Talking with Steve, the Absolutes like faster burning powders, not normally associated with the cartridge size. They need to pressure up faster since the ogive and "bearing surface" are actually undersized,and do not contact the lands. Only the drive bands do.

I am running the 129 AH in my two 6.5SSs (20" & 26", both 1:7.5") over H4350. Amazing results with H4350. Great accuracy, good velocities too. I would try a faster powder.

Just some insight here, I'm running the 116AH in a 270AI and the load I'm using is a max load for a 90g bullet in the Hogdon manual

 

[Idaho Hunter1]

Talking with Steve, the Absolutes like faster burning powders, not normally associated with the cartridge size. They need to pressure up faster since the ogive and "bearing surface" are actually undersized,and do not contact the lands. Only the drive bands do.

I am running the 129 AH in my two 6.5SSs (20" & 26", both 1:7.5") over H4350. Amazing results with H4350. Great accuracy, good velocities too. I would try a faster powder.

I'll try this this week. Thx

 

[GLTaylor]

Go to a faster powder. Try down in the RL16, 4350 or H100V range.
G

 

[dougduey]

Lots of good advice from the crew here.
Faster powder is where I would start.
I've only had to play with seating depth in one rifle, so that's probably last ditch effort from my experience.
You may want to drop down to the 124 Hammer Hunter instead of the Absolute. I've found the Hunters shoot better than the Absolutes in a couple of my rifles, although the difference is .20 moa compared to .60 moa.
Might try the 109 Absolute. It's a laser out of my 6.5-284 at 3511 fps and sub .50 moa.