I need a little guidance on where to go from here. Trying to decide between 130 vlds and 140 hybrids or at least where to go from here. Here is my progress thus far. All loads listed are with hornady factory brass from pulled 120 AMAX ammo w/ factory primers. Final workup but the intention of the rifle was to shoot the 140 hybrids over h4350 and fgmm 201m primers in hornady brass w/ .0002-3 neck tension.
130 VLD OAL work up
130 VLD's Seated into the lands have a coal under 2.82 and thus can fit into a 308 p mag. So my first step was to pick a charge and do a work up to find the best seating depth. This consisted of 4 rounds over 42.5 gr of h4350 for each seating depth, seated at 0.015, 0.030, 0.045, and 0.060 off the lands. It seems that both 0.015 off and 0.045 off both deserve a retry to determine if either group would improve with better shooting and I could then take either and do a charge work up to see if either will group at a higher charge weight.
140 hybrids
These were more problematic. Using again the Hornady OAL gauge and several 140 gr hybrids to find max OAL. They were failry consistent but these bullets had a COAL of roughly 2.91, well outside of the capacity of a 308 p mag. Since this is a semiauto, magazine feeding is pretty important to me. So I loaded up a set of charges seated to COAL of 2.81, which was one tenth of an inch shorter than the depth seated into the lands. While hybrids are listed as jumpt tolerant, one tenth off the lands seems a bit excessive but i tried it anyway. The charges varied from 40.8 to 42.7 increasing charge weight in .3 grain intervals. and the and these are the resulting 3 shot groups
There were no signs of pressure that I could see but below is a picture of the brass, with loads increasing from left to right.
Now my dilemma, 130 vld's or the 140 hybrids. I originally spent the extra for the extra cash for the JP bolt in order to push the 140's with enough speed to justify them over the 130 vld's. Based on my results however it seems that despite the lack of pressure signs, the bullets aren't grouping as well. Any suggestions on how to proceed?
Gun specifications
Aero M5 upper/lower set
CMMG LPK
ALG ACT trigger w/ JP yellow trigger spring
JP High pressure bolt w/ dpms bolt carrier
22 inch 6.5 creedmoor Kreiger barrel w/ fox river brake
- barrel was reamed with SAAMI minimum reamer from Hornady and Creedmoor sports by Kreiger against my bolt.
Syrac low profile adjustable gas block w. rifle length gas tube
Midwest Gen 2 SS 15 inch handgaurd
Magpgul AR 10 PRS
Rifle length extension, 308 dpms rifle buffer, JP OCR spring
weaver 20 moa riser
Sightron S3 6-24 mh reticle
130 VLD OAL work up
130 VLD's Seated into the lands have a coal under 2.82 and thus can fit into a 308 p mag. So my first step was to pick a charge and do a work up to find the best seating depth. This consisted of 4 rounds over 42.5 gr of h4350 for each seating depth, seated at 0.015, 0.030, 0.045, and 0.060 off the lands. It seems that both 0.015 off and 0.045 off both deserve a retry to determine if either group would improve with better shooting and I could then take either and do a charge work up to see if either will group at a higher charge weight.
140 hybrids
These were more problematic. Using again the Hornady OAL gauge and several 140 gr hybrids to find max OAL. They were failry consistent but these bullets had a COAL of roughly 2.91, well outside of the capacity of a 308 p mag. Since this is a semiauto, magazine feeding is pretty important to me. So I loaded up a set of charges seated to COAL of 2.81, which was one tenth of an inch shorter than the depth seated into the lands. While hybrids are listed as jumpt tolerant, one tenth off the lands seems a bit excessive but i tried it anyway. The charges varied from 40.8 to 42.7 increasing charge weight in .3 grain intervals. and the and these are the resulting 3 shot groups
There were no signs of pressure that I could see but below is a picture of the brass, with loads increasing from left to right.
Now my dilemma, 130 vld's or the 140 hybrids. I originally spent the extra for the extra cash for the JP bolt in order to push the 140's with enough speed to justify them over the 130 vld's. Based on my results however it seems that despite the lack of pressure signs, the bullets aren't grouping as well. Any suggestions on how to proceed?
Gun specifications
Aero M5 upper/lower set
CMMG LPK
ALG ACT trigger w/ JP yellow trigger spring
JP High pressure bolt w/ dpms bolt carrier
22 inch 6.5 creedmoor Kreiger barrel w/ fox river brake
- barrel was reamed with SAAMI minimum reamer from Hornady and Creedmoor sports by Kreiger against my bolt.
Syrac low profile adjustable gas block w. rifle length gas tube
Midwest Gen 2 SS 15 inch handgaurd
Magpgul AR 10 PRS
Rifle length extension, 308 dpms rifle buffer, JP OCR spring
weaver 20 moa riser
Sightron S3 6-24 mh reticle
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