I know the usual barrel length on the LRP-07 factory builds is 20-22" and the max length handguard is 17.25". Has anyone used anything longer, like a 24" barrel? If so could you drop a pic and how was the balance of the rifle with the slightly longer barrel? I want to go a little longer one one of my barrels for this build so that my velocities may be a little more consistent with online load data since most are based off a 24-26" barrel.
JP LRI-20/LRP-07 with longer barrel
- Thread starter PRSDietitian
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I was just looking on JPs site the other day and noticed they now have heavy profile 24" 6cm and 6.5cm barrels available; that's something I have not seen them offer before. They typically used to offer light and medium profile barrels from 16" to 22" on the large frames, that's all that was available when I ordered my 2 LRP07's several years ago. Not sure if you can order the 24" heavy barrel on a rifle or upper assembly, but you can order it as a barrel kit.
One of my LRP07s has a 22" medium profile barrel and it balances out pretty well with a Magpul PRS stock, maybe a bit butt heavy. My old armalite AR10 had a heavy profile 24" barrel on it similar to that JP barrel I linked above, and it was a bit nose heavy IMO even with a heavy PRS buttstock, but it was easy to handle and shot well. If I was ordering my LRP07 today I think I'd go with the 24" heavy barrel.
I still want to swap out the barrels on my 2 6.5cm LRP07s as they have rifle length gas ports and are a bit hard on the brass no matter what buffer spring/weight and gas block setting, but rifle length gas was the only way JP made their 6cm and 6.5cm barrels at the time. Debating if I should just get 2x +2" gas port barrels and longer handguards for my current non semi monolithic uppers, or order 2x complete new semi monolithic uppers.
One of my LRP07s has a 22" medium profile barrel and it balances out pretty well with a Magpul PRS stock, maybe a bit butt heavy. My old armalite AR10 had a heavy profile 24" barrel on it similar to that JP barrel I linked above, and it was a bit nose heavy IMO even with a heavy PRS buttstock, but it was easy to handle and shot well. If I was ordering my LRP07 today I think I'd go with the 24" heavy barrel.
I still want to swap out the barrels on my 2 6.5cm LRP07s as they have rifle length gas ports and are a bit hard on the brass no matter what buffer spring/weight and gas block setting, but rifle length gas was the only way JP made their 6cm and 6.5cm barrels at the time. Debating if I should just get 2x +2" gas port barrels and longer handguards for my current non semi monolithic uppers, or order 2x complete new semi monolithic uppers.
I’m saying this, just because I love the semi monolithic upper, I would get the latter of the two. I have a shilen blank going to Paul Ross for a custom ultra heavy contour
I’m saying this, just because I love the semi monolithic upper, I would get the latter of the two. I have a shilen blank going to Paul Ross for a custom ultra heavy contour
I'm tempted, but the current cost of just a new complete semi monolithic upper is nearly what I paid for the complete rifles about 8 years ago, lol. They shoot great with the "old" uppers, not sure how much the semi monolithic uppers can improve things, but I do see them being stiffer and helping with heavy contour barrels.
yeah they support the barrel more and less flex between the receiver, barrel nut, barrel, and handguard
im getting a 22" 1.20 for the length of the barrel till you get to the gas block journal where it goes down to .936, the, down to .775 about 1.95" before the thread shoulder at the muzzle for a griffin PSR-7 suppressor brake
im getting a 22" 1.20 for the length of the barrel till you get to the gas block journal where it goes down to .936, the, down to .775 about 1.95" before the thread shoulder at the muzzle for a griffin PSR-7 suppressor brake
I decided to go with the JP receiver, and hand guard route only because Seekins no longer sells SP 10 builder kits. Sure I could get a used SP 10 and upgrade the barrel, but in the grand scheme of things I would actually be spending more money going that route compared to what I’m actually going to be doing.
I have a shilen blank on order Simply because the wait time on a 1.250 or a 1.20 street blank from Krieger or Bart Is a lot slower and I went to Bugholes and Bullet Central, and none of them had a 1.25 straight or 1.20 Straight in 6.5 that was able to be sent out right away
That being said, because the JP barrels do in Include the bolt, you’re probably looking at like $550 for the barrel. Although I don’t know who they get their blanks from.
I have a shilen blank on order Simply because the wait time on a 1.250 or a 1.20 street blank from Krieger or Bart Is a lot slower and I went to Bugholes and Bullet Central, and none of them had a 1.25 straight or 1.20 Straight in 6.5 that was able to be sent out right away
That being said, because the JP barrels do in Include the bolt, you’re probably looking at like $550 for the barrel. Although I don’t know who they get their blanks from.
Are you shooting PRS? Only reason I ask is do you need the larger diameter barrel for weight?
I had the same issue with a proof 6 arc barrel I just used to build a PRS gas gun. Ended up putting 2 sets of these on there and now it's perfectly balanced: https://l3idesignsolutions.com/product/m-lok-brass-weight-set/
I had the same issue with a proof 6 arc barrel I just used to build a PRS gas gun. Ended up putting 2 sets of these on there and now it's perfectly balanced: https://l3idesignsolutions.com/product/m-lok-brass-weight-set/
Yup mostly PRS not so much ruck matches. But I could use more weight for cardio workouts I guess
My buddy Phil Decker recommended those same weights
My buddy Phil Decker recommended those same weights
Cool, thanks.
Just noticed JP has a few "limited run" cut rifled barrels available right now; 6cm heavy contour 24" with a +3 gas system, 6cm 22" medium contour with +3 gas system, and 6.5cm 22" medium contour with +2" gas system.
Whenever I get around to rebarreling my 2x LRP07s I need to decide if I want to stick with my current uppers or get the new semi-monolithic uppers, and if I want to stick with JP barrels or maybe go with Bartlein from Craddock.
I have 2x SCR11s and 2x LRP07s and all 4 of them are very accurate and easy cleaning with the factory JP barrels, but there's a lot more options for barrel lengths, gas port lengths, and contours from someone like Craddock. I have zero accuracy complaints with either of my LRP07's right now other than the rifle length gas ports are hard on brass regardless of buffer weight or spring rate combo even after trying multiple powders. Wish JP was making their barrels with +2" gas ports when I bought them, but 8 years ago when I ordered them 6 & 6.5 CM AR's were still kind of new and everyone was still figuring them out and using large firing pins and rifle length gas systems. My 6.5CM GAP10 that I had just before the JPs pierced primers like crazy with factory 140 Amax ammo because the early 6.5CM GAP10s used large firing pin bolts, and after a piece of primer stuck the firing pin and it ran away full auto slam firing it went back to GAP twice, and the second trip back they switched it over to an Armalite bolt and extension because the Armalite bolt used a small firing pin. GAP started using SFP bolts on new 6cm/6.5cm GAP10s going forward, and around the same time JP started selling their small firing pin "high pressure" bolts. My first LRP07 came with a large firing pin bolt but I switched it to a small firing pin high pressure bolt as soon as JP started selling them.
Don't post crap like that, you're going to make me spend money on 2x new LRI semi-mono uppers that I'm still not convinced are really needed over my current uppers, but look really cool.
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Pictures like those are dangerous…Don't post crap like that, you're going to make me spend money on 2x new LRI semi-mono uppers that I'm still not convinced are really needed over my current uppers, but look really cool.
Pictures like those are dangerous…
Yes they are.
I know I'd be perfectly happy and would save a bunch of money just rebarreling my current older LRP07 uppers, but the new LRI uppers are nice and make the barrel nut and handguard installation easier, not to mention the supposed stiffness gains.
Wonder if JP would sell me bare LRI20 uppers and not have to buy complete upper assemblies. I know they're helpful and can often handle requests for stuff not on the website if you call them, as one of my LRP07s is setup with a light contour 20" 6.5CM barrel for hunting use-- that was a non-standard barrel contour they made for me.
So the balance point is the same between the LRI-20 24" and the SP10 22" Bartlein barrel, both barrel have the exact same Contours.
As for velocity, it's a 28-FPS gain on the JP
Both riflesshpot the same load of 40.4grs H4350/ Lapua SRP Brass / 140 ELD / CCI BR4 primers.
SP10 DATA
Any of these work well, I'm kinda on a ATACR kick right now since Scheels price matches EV. So the ATACR'S are growing in numbers.
What contour is that barrel? Any fluting?
Definitely balances much further forward than my LRP07 with a 22" medium contour JP barrel and PRS buttstock, and that's a good thing IMO.
Definitely balances much further forward than my LRP07 with a 22" medium contour JP barrel and PRS buttstock, and that's a good thing IMO.
Your build is probably the closest to what I’ll want for my 2nd barrel. The first barrel has to have a smaller contour towards the end for the PSR7 suppressor. But after that, it’s basically going to be a 1.20 straight down to .936 at the gas block which is rifle +2 and then it’s gonna be the same contour through the muzzle. And yes, I do plan on using this rifle in matches that require rucking Because I to like to torture myself
