How much longer ya gonna make us wait? Have ya shot your JP yet? Would like to hear your thoughts on the two rifles.
The JP arrived while my GAP10 was back at GAP for piercing primers. Summary: GAP switched out the DPMS-style bolt with a .080 firing pin to an Armalite bolt & barrel extension as the Armalite bolts use .068" firing pins which took care of the issue. Long version here including good input from George:
http://www.snipershide.com/shooting...vy-swipes-2-pierced-primers-factory-ammo.html
While the GAP10 was back at GAP for testing and ultimately the bolt swap the JP arrived and I started shooting the JP. I can't make a fair comparison yet as the GAP10 has never run reliably until the bolt swap. I haven't shot the GAP10 since it came back other than a couple of rounds behind the house to test the new bolt because while it was back at GAP for the work I swiped the S&B 5-25 that was on it and put it on the JP. Now the GAP10 is sitting back in the safe waiting for a scope. Right now my experience with the GAP10 is limited to the few trips to the range before the bolt swap and those impressions are that it's quite accurate when I wasn't stripping the bolt to pick out primer pieces (which was about 3-5 times per mag with the original DPMS bolt.) I need to pick up another scope for the GAP10 (probably a Bushnell XRS) and then I will hopefully have a more favorable experience with the rifle; with Armalite bolt I won't have to strip the bolt & remove primer pieces from the bolt 3-5 times per 10 round mag. The few rounds I shot behind the house after getting the rifle back from GAP showed flattened primers with 140s over 43.0gr H4350 but the firing pin impact was perfect. That load would have been 100% pierced primers with the original bolt so I'm very confident the problem is solved.
I can't make the call until I get another scope and shoot the GAP10 more but here are my feelings right now....
The JP has nicer fit/finish, not that the GAP is bad-- it's really nice actually but the JP is just damn near perfect. The side charging handle on the JP is super nice to use without breaking cheekweld. I like the ambi bolt release on the GAP and wish the JP lower had one. I could always add a Phase 5 or similar extended bolt release to the JP but I prefer one integrated into the lower like the GAP10. The JP is a little lighter than the GAP10 for those of you concerned about weight.
The fit & finish of the JP bolt and LMOS carrier makes the bolt & carrier of the GAP10 look pretty "industrial" in comparison. The GAP bolt/carrier are perfectly functional and are your typical AR fit & finish but setting them side by side it's obvious JP puts a lot of time & attention into fit & finish-- their bolt & carrier are impeccably finished & polished and very smooth cycling.
The JP silent captured buffer is really nice too, it's very smooth with no noise up through the stock while cycling. I picked up another JP silent captured buffer to try in the GAP10 along with the spring pack for tuning since the GAP10 doesn't have an adjustable gas block.
The JP has a lighter/smoother/faster recoil impulse shooting the same loads, probably because the JP brake is bigger than the GAP titan brake on my GAP10 and also because the JP has the low mass operating system compared to the heavier carrier & buffer in the GAP10.
Accuracy wise they're both very close but I'd give a very slight edge to the GAP10 for accuracy-- but we're splitting hairs at this point, both rifles are extremely accurate. The JP and GAP10 have both managed several 1/2 MOA 5 shot groups at 500M when I'm having a good day on the gas guns... I have no problem admitting I'm not the most consistent large frame AR driver. While I'm quite consistent with my JP SCR11's (.223) I'm about 70/30 for good and bad days behind the large frame ARs. I need more practice in that department!
I'm still tweaking loads on the JP; while the 140 Amaxes shot very well including several 1/2 MOA groups at 500M the the rifle was having occasional failures to eject. Ben @ JP said they had seen cycling issues before when using 140s and suggested using 130s, 123s, or 120s as the 140s are a little tough on a gas gun. George suggested the same thing about running 140's in the GAP10 when I had the pierced primer problem, he strongly suggested sticking with 130s or lighter. So far I've tried 130 VLDs and 123 Sierras in the JP. It liked the VLDs and had a couple 1/3 MOA groups when doing load testing at 300Y but it hated the Sierras and struggled to hold 1 MOA at 300Y. I just finished loading up some 123 Scenars along with some more 130 VLDs to test. The 22" barrel on the JP maxed out about 2745fps with the 140 Amax and did show minor pressure signs when pushed that hard, it was much happier down around 2680fps for both accuracy and brass condition. I've pushed the 130 VLD's to 2840 with 43.5gr H4350 with no pressure issues and the 123 Sierras made it up to 2960 with 44.8gr H4350 before showing minor pressure issues. The sweet spot with the 130 VLD's seems to be right about 42.9gr H4350 / 2790 fps. I won't know if the rifle likes the 123 Scenar's until I try them.
While they're not released yet I'm looking forward to the Berger 130 Hybrid, higher BC than the 130VLD.
One thing to keep in mind is the JP uses the larger .080" firing pin that was nothing but trouble in the GAP10; however the JP has yet to pierce a primer. Where the .080" firing pin in the GAP10 left nasty high ragged craters (when it didn't pierce the primer) in the JP the .080 firing pin impact has a slightly raised but very smooth ring around the impact.
One last thing that I should mention is both GAP and JP have great customer service. While I haven't had anything other than minor questions for JP regarding the occasional ejection issues they were easy to get a hold of and I chatted with Ben for about 30 minutes-- very nice and knowledgeable guy. Ben did ask for me to follow up if the 130s or 123s fixed the problem or if I was still having issues they would either send me a new ejector & extractor to try or a shipping label to send the rifle back for inspection. My experience with GAP regarding the primer issue was a little more in depth than just a chat since the rifle had to go back-- they were awesome to work with and they swapped the barrel extension & bolt, tested it, and returned it in a timely manner while keeping me up to date with everything they were testing and trying. Josh from GAP PM'd me soon after I posted my initial questions about the issue before I found some free time to call them!
You really can't go wrong with either rifle IMO, but the final verdict on which one I prefer will have to wait until I get another scope for the GAP10 and do some load development with 130s for it. It was very accurate with the 140s and I expect the same from the 130s. The bolt swap should take care of the primer & reliability issues I experienced early on. I have a feeling I'm going to end up keeping both-- even if it does mean I have two rifles that for all practical reasons are nearly identical.
