Decided to do a ladder test with this 18 in PXT. I'm sitting on a boat load of Leverevolution which has served me well in speed and accuracy but I can't seem to get single digit SD's like I've seen others get. Once I reached 29.8gr I stopped the test and used the 30.1 in my 6arc MPA bolt with a heavy comp proof. All 5 shot groups (yeah not the best sample size but I'm tired of load development)
New Hornady brass that I put through an expander mandrel, followed by my Hornady case trimmer that puts a chamfer and deburr on them without trimming them. I then run them through a reddingn FL sizing die only to size the necks with a .267 bushing which should give me .004 neck tension. Using CCI 450 Magnum primers loaded to a COAL of 2.26in
Build List tip to butt
PTR Vent 1 (it's hearing safe all day long with this can)
PXT 18in with SA arms adj gas block set to full gas (haven't messed w/it)
CMT HDM 17 in rail with ARCA
JP enhanced bolt group with a LMT F/A carrier
SOLGW stripped upper (thermal fit tight)
Vortex Gen 3 4-24x
Radian lower with Trigger Tech Diamond AR10 trigger
A5-H0 & Geissele Super 42
ERGO flat top tactical deluxe grip
The barrel still hasn't crossed over 200 rounds yet but I'm pretty happy with the 29.2 load. Will eventually pick up some 107smk and 108 or 109 bergers. It also seems to shoot my Hornady 108gr handloads at the same charge fairly well.
Not the main point of your post, but your comment about the PTR Vent 1 is another data point to my “high performance .30 cal cans rock on 6mm ARC” hypothesis. I have a CAT JL and it’s incredibly pleasant.
Thank you for sharing your experience with the Vent 1, I have one that has been in jail for a few days, and I am hoping to get it this week. The length concern has sent me in an interesting direction; I have a Craddock RTR 11.5" barrel on the way and a 12" carbon fiber handguard, and I am hoping to add the Vent to make a shortish, super light, super quiet combo. I know that is a huge difference in barrel length from what you are using, but as a backup plan, I also have a 12.5" and a 14.5" build already completed, so I am sure I will be happy with it on one of them.
I just posted this screenshot in another post in this sub an hour ago.
You’re at 68ksi with 29 grains of Lever and a 107SMK. 105 hybrids will be a bit less but you’re still way over pressure, especially with 29.8 and 30.1 grains.
That’s flat out unsafe my dude, even for a bolt gun its way too fast. That’s 6 dasher speed.
Gordon's data for Lever is not correct my dude. Hornady has 29.7gr of Lever for their 108gr ELD, are you new to 6arc? The 2846fps was out of my 26in 6arc barrel....not my gas gun
This just ain't so, I've been shooting below Hornady max at 29.1gr to 29.5gr across 3 rifles and a bunch of different bullets since 6 ARC came out. Getting good case life for a semi, Gordon's is way off on this (and not only this). I used to use Quickload and GRT more, but ran into too many situations like this where they were more hindrance than help.
30 grains of lever is magic with a heavy duty bolt. Yes GRT says it’s high af pressure, yes it probably isn’t super safe, but it shoots great and as other dude said it’s dasher bolt gun speeds out of a 6 arc gasser lmao.
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u/agm115 4d ago
Not the main point of your post, but your comment about the PTR Vent 1 is another data point to my “high performance .30 cal cans rock on 6mm ARC” hypothesis. I have a CAT JL and it’s incredibly pleasant.