jp enterprise vs shilen

[Kilco]

Gents, I was hoping for some input on the jp supermatch barrels specificly compared to the shilens. I have contacted shilen and realize they don't use a SAMMI spec chamber, yet I find it hard to believe AA would put there stamp on one if it weren't approved my Bill Alexander himself. The JP barrels I believe are true SAMMI spec, yet I cannot confirm this. I'm looking at the 22" specificly, and notice they use a 1:8 twist wile shilen used the AA recommended 1:9 twist. Also unsure about the bolts that jp sends with their barrels. Any input would be appreciated, thanks.

[Keep The Change]

I'm pretty sure JP uses SAMMI spec and as far as quality, I don't think you can go wrong with JP.
But I'll step out of the way for those that have the actual hardware or know for sure.

[SG4247]

I will not buy anymore Shilen barrels or barrel blanks.

JP barrels will shoot circles around Shilen.

The chamber is not as big of a deal - as the barrel manufacturing (rifling) quality is. All the JP barrels I've seen were awesome.

Personally I prefer the non SAMMI chamber, but the SAMMI chamber is fine also.

ALSO: JP bolts are the best in the business.

[PredatorDown]

I can't speak for the Shilen, but I absolutely swear by my 22" JP barrel. Seems like all I had to do with load development was pick a powder, seat the 123 amax to mag length, shoot MOA or better. My pet loads shoot 5/8-3/4" with over 3500 rounds down the tube. After some tinkering I also found that my barrel likes a big jump with the 123 amax. I can seat to mag length of 2.26 comfortably, but it shoots best at 2.235 OAL

[rabiddawg]

Shilen themselves may not use the saami chamber but I have read here that AA does ALL the machine work on rifled blanks. So I'm sure AA uses the correct chamber. Can you not buy the shilen from AA?

EVERY person on this board that shoots a jp has posted nothing but positive comments.

[Kilco]

Thanks for the input guys! When I first decided to roll Grendel, I ordered a 20" AA entry upper. Luckily I was able to get it sold before it landed, and decided to just replace the barrel and bolt on a 556 I no longer use. I was looking at the shilen combo at midway usa at first, then my local gunsmith, 6.5 nutjob, and dealer (my father) told me we are a JPrifles dealer, and had nothing but good things to say about the 260 barrel on his armilite ar-10. We can get the JP 18 and 22 with bolt for just slightly more than the shilen combo.. I knew the Horde would have some good input in this. Im using a MI Gen 2 SS handguard on that rifle, with a .750 LP gas block. Is the handguard, barrel nut, and gas block compatible with the JP heavy 22"? Also anyone with current JP experience know what the standard roll over time is for a barrel/bolt combo? The website says 1-2 weeks, but that seems very optimistic.

[PredatorDown]

Great minds think alike...your upper will be very similar to mine. I love the MI Gen2 SS handguard, but it's a pretty tight squeeze to get that heavy barrel in there. No room for an adjustable gas block, but most low profile blocks should work fine. It'll need a .936" block instead of a .750" though

I'm not much help on current lead times since I ordered mine close to 2 years ago, but when I did it was just over a week

[Vasux86]

I have been a step away from ordering a jp barrel on two separate occasions. Both times I called to check on the lead time and they informed me barrels were shipping in less than a week. I would consider contacting them so you can hear it straight from the horses mouth, but my guess is you could get a jp barrel as quickly, if not much quicker, than any other barrel.

[Drillboss]

Let's not slam Shilen too hard about not using a SAAMI chamber. I believe they use an AA reamer design from before SAAMI certification. Best I can tell, it's within a few thousandths of SAAMI and uses the same 0.3" neck and the compound throat. Here's a copy of the reamer drawing they sent me about a year ago.

Pacific Tool 6.5 mmGrendal (AR).pdf

[Kilco]

Great minds think alike...your upper will be very similar to mine. I love the MI Gen2 SS handguard, but it's a pretty tight squeeze to get that heavy barrel in there. No room for an adjustable gas block, but most low profile blocks should work fine. It'll need a .936" block instead of a .750" though

I'm not much help on current lead times since I ordered mine close to 2 years ago, but when I did it was just over a week

Good info! What kind of gas block did you roll with? And just to confirm, the MI barrel nut works fine with the medium contour JP?

[LRRPF52]

Let's not slam Shilen too hard about not using a SAAMI chamber. I believe they use an AA reamer design from before SAAMI certification. Best I can tell, it's within a few thousandths of SAAMI and uses the same 0.3" neck and the compound throat. Here's a copy of the reamer drawing they sent me about a year ago.

[ATTACH]7648[/ATTACH]

That looks like a SAAMI chamber to me, since you have the .300" neck, .2644" dia. just in front of the neck where the freebore is, and then a .2617" dia. at the point where the target leade begins. You also have a .153" initial compound leade length, the same as the SAAMI. Only difference I'm seeing on cursory inspection is the .2644" initial freebore dia. vs. .2645" on the drawing we have in Volume I, which is .0001".

Shilen makes great barrels. JP sells great finished barrels. JP does deep cryogenic stress relief on them, which many people feel is worthless, but then the JP barrels shoot, and hold groups very well under rapid fire, even from thin barrels, so I think JP knows what he's doing.

He's one of the few names in the industry who still competes, and has been competing in action-based precision matches for decades now.

[Drillboss]

The max headspace dimension is 1.2251" for the PTG reamer versus 1.2301" for SAAMI. The length from the bolt face to the 0.2617" throat diameter is 1.7008" for PTG versus 1.7025" for SAAMI.

Looks to me like these dimensions were relaxed slightly when it went to SAAMI.

[PredatorDown]

Good info! What kind of gas block did you roll with? And just to confirm, the MI barrel nut works fine with the medium contour JP?

Honestly not sure on the gas block, had the local gun shop throw it together for me. Doesn't look to be anything special, just the run of the mill low-profile gb. Same goes for the barrel nut. As far as I know they didn't have any issues with it.

[molar]

I can testify that Shilen barrels turned and chambered by AA will flat out shoot. My 20" Shilen barreled advanced entry upper will shoot 5 rounds of factory Hornady Amax's into 0.4" @100. Now some of that may be due to the fact that AA trues their uppers and beds the barrel as well as the gas block, but the barrel still has to be great to do that consistently.

[Hoser1]

Go with the JP 22" you won't be sorry. The quality and fit and finish of the JP barrel is top notch, easy to clean, and makes for a fairly light build even though you have a 22" barrel. I put JP's adjustable clamp on gas block and have not had any issue's. He send really good instructions on how to install and set up his gas for gun that cycles time and time again. I have AA side charging upper and the fit between the 2 was very tight. Had to use a dead blow go get the barrel to seat. I truly haven't found the sweet load that I'm looking for, but 95 gr amax's shoot really well from my rifle.