Jump to content
Brian Enos's Forums... Maku mozo!
Smokecloud

AR10 in 260 Remington

Recommended Posts

I have had a set of Aero Precision AR10 receivers for about 2 years now just sitting on the shelf from a political panic buy.  I have a few different builds going on already, but I kept looking at starting that gun.  I have been watching the threads here for sometime regarding a couple of 6.5 CM builds.  I finally narrowed my decision down to either 6.5 CM or 260 Remington.  I have had a couple of long phone calls with friends on the matter and decided that the comparison was a wash.  More factory ammo available for the CM, but I will probably never buy more than a box or two of factory ammo, since I reload pretty much everything I shoot for.  It was almost down to a coin flip because of the differences and pros vs cons of both.  I decided that the 260's case profile looks like it would probably feed better in a semi-auto platform, plus with the buckets of 308 brass laying around, in a pinch, I could probably make my own brass if things dried up again.  I decided to swing to the 260 side, but just barely.  I'm looking at this build as a long range toy and to use on occasional match stages as a bonus gun, or for whatever.  I don't care if its heavy, I'm not building it to run and gun with, most likely as a bench gun or shooting from stationary positions.  It would also be nice as a trainer for my boys, as it will be very low on recoil.

To make the decision permanent and end 6 months of fretting and 2nd guessing, I ordered a barrel.  I opted for a 24" all steel barrel from Proof Research.  It came with a 16 week wait, sooo, sometime in maybe February.  Those barrels are head spaced off of the JP HP bolt, so I ordered one of those as well.  Has anyone here built one of these?  I have built over 100 small frame AR's but have only worked on a few of the large frame's and this will be my first ground up build of an AR10. So far, everything I have is DPMS pattern parts.  I was glad that I waited to order the barrel, because even though it was not advertised, I'm told that mine will be there newest version where they have moved the gas port an extra 2 inches out (plus 2 version). 

I have to chose a bolt carrier, but hate to pony up for the JP.  The JP/HP bolt was already over $200 and I'm not real excited about having $450 into a complete BCG.  Is there a better similar carrier for better price? I will need to find the XL length gas tube and chose a gas block.  I want to put an adjustable gas block on this rifle, does anyone have a favorite that they prefer for this type of setup?

Share this post


Link to post
Share on other sites

I built a 6.5 Creedmoor in the same set up.  I did use all JP parts, including the barrel.  Only shot a few rounds through it, but the factory Hornady ammo was very accurate.  Wish I still had it.

Share this post


Link to post
Share on other sites

I did a .260 build earlier this year, I went with all JP Barrel, Low mass b/c, captured spring buffer, and I used a non adjustable gas block originally. That resulted in major over gassing, replaced the block with a Superlative gas block and everything was great.  I'm shooting .5-.6 groups w/ 140SMKs.

Share this post


Link to post
Share on other sites

I will look into the Superlative block, thanks for the suggestion.  I originally looked at the JP stuff, I have run it from time to time and its always top notch, they have been the measuring stick for a long time and were just about the only game in town for builds like this.  With a little pushing from friends and simply wanting to try something different, I decided to go with the Proof barrel.  I didn't need a forward assist on the upper receiver, but its there.  I keep looking at the Aero Carriers because the cuts work with the forward assist.  I recently emailed them and asked if they sell just the carrier, they replied no.  I will probably just end up buying a JP carrier, but will have to consider the LW vs the standard weight.  I am looking at using a Hyperfire trigger, I believe its the only way to get a good trigger in an AR10 package that will pull under 3lbs.  My brother has been running one for 2 years now in one of his builds and its just under 2 3/4 and is amazingly better feeling than any of my other various triggers.  What kind of brass has given you best the combination of case life and quality?  I'm not sure how destructive this sort of setup will be on brass, so I'm not sure if I want to pony up for Lapua, or get something more reasonably priced because its short lived anyhow.  I have an M1a that pretty much wrecks the brass in 4 firings for comparison.

Share this post


Link to post
Share on other sites

I recently helped my gunsmith with my AR10 6.5CM rebarrel job. I love the big AR. Mine is an Armalite pattern. I wanted a 6.5CM autoloader for the same reasons you do. I'm running an adjustable gas block, and I'm running a standard weight BCG with an agresive muzzle break. Recoil is very mild and I can watch the impact through the glass. 

You might want to read up on issues with the big ARs trying to run a LWBCG. There are several threads on cycling issues. One of the guys I shoot with tried a LWBCG in his DPMS pattern AR10 in .308. He never did get it to run with the LWBCG. He put the standard weight BCG back in and it ran fine. I don't know about the DPMS lowers, but the Armalite lowers take any AR trigger you want.

I use both factory ammo and my reloads including some .308 brass I necked down to 6.5CM. Accuracy is great with any of the brass behind the 140g bullets from Hornady or Sierra. I'm really glad I rebarreled the AR10 to 6.5CM.

Share this post


Link to post
Share on other sites

Well.....I have built BOTH 6.5s in Creedmore and 260 Remington.  From a shooting standpoint, its a wash.  I do reload both, and compete in LR precision bolt regularly with both rounds.  Typically, I will "retire" my bolt brass, full size them, load them differently, and then feed my gassers with the older brass as these rifles are hard on the brass.  (Different loads are required for the Gassers vs the bolt guns of course)

Recently, the price for Hornady 6.5 ELD-M rounds has fallen to as low as $1.20 a round, and Prime ammo is also available in bulk for a bit more.  At these prices, it is just not worth the time and effort to feed the Gas guns by doing hand loads.  Moreover, the brass can be reused from the factor ammo as well.  

So - given current pricing, I would opt for a 6.5 Creedmore. I can still reload, but have the option to shoot quality factory ammo as well. 

Note - be certain to purchase a high quality "adjustable" gas block, as you will end up spending some time getting it to cycle properly with the HP loads.

Enjoy - you will have the best grouping ARs around.

 

Share this post


Link to post
Share on other sites

Thank you to both replies, there is a wealth of information between the two posts.  I have been reading everything I can get on the topic and have found issues regarding LW carriers and figured I was back at the decision for the standard weight, but notice that JP only offers an extra heavy version, so that is probably what I will set my sights on, really that is what I have done with most of my builds.  I usually favor the heavy route for several reasons.  I looked at the superlative and may consider that for a SBR build sometime, but i'm not crazy about venting gas out of the block since I will more likely than not, have it covered with a handguard, which will soot up stuff at some point.  I'm thinking about just sticking with JP for one of their adjustable blocks, any other brands I should consider?  I have ran Seekins on a couple of the small builds, they seemed to work fine.  I may run a suppressor on the 260 at some point, which always requires a drastic gas change.

 

Looking at the price of new brass, Lapua runs just short of a buck per case, so its not very appealing.  Norma would be my 2nd choice, but I haven't checked to see if they even make brass for the 260.  I would only consider those for trying to squeeze the most out of the package.  It's nice to hear that the 260 is not that finicky, some of those calibers are very hard to nail the perfect load on.  I will check out the Prime Ammo, what brass do they use?  If I go with the JP contained buffer spring system, should I stick with a standard carbine buffer tube, or opt for the full length version?  I see it comes with a spacer that should make it a wash.  I'm looking at the Magpul or equivalent stock that is adjustable for cheek weld. 

 

I have found several articles and other write up's on the pressure problems of running the heavier bullets with the slower powders, it makes sense with the med burn rate powders, but seems like almost a non-issue with the +2 gas system if I run an adjustable gas block.  This will be a slow build, but please keep the tips coming. 

Share this post


Link to post
Share on other sites

I have built 260s and 6.5s using both JP and GAP.  You really cant go wrong with either company - JP support has been fantastic and Ive even had JP himself email to check on things.  With GAP, they delivered their built ahead of time, but Ive never needed to call on support - so - Good things to say about both companies!

Big fan here of Lapua brass - will always use it when available.  

 

Share this post


Link to post
Share on other sites

I have a 6.5 Creedmoor. I haven't really shot it beyond one box of Hornady hunting ammo. It seems quite accurate even using factory cheap ammo. It has a McGowen 24" custom barrel. It did not run correctly when first assembled. Was way overgassed. However despite not using a JP HP bolt for initial testing, primers and brass were fine. I am planning to fit an adjustable gas key.

 

As for adjustable blocks, SLR, Superlative Arms, Odin Works - all make a good product. My most recent build used a Odin Works, which is adjustable from the front with detents. Worked great, and was cheaper.

 

As for buffer tube, I would use a VLTOR A5 tube, AR-10 carbine spring, and H3 carbine buffer. I have used multiple systems - the standard A2, the AR-15 carbine tube with the DPMS shorty 308 buffer, and the above setup. That, or the A2, has yielded the best reliability and felt recoil.

 

The workup for my 6.5 loads is going to focus on 123 Amaxes and Varget/RL-15. This seems like the best combo for a gas gun, and easiest on brass. If I was going to spend more $$$ I would also consider the Berger 130 Hybrid.

Share this post


Link to post
Share on other sites

Good luck with the 123gr Amax's. They're discontinued. The new ELD's have a better BC but a higher price to go with it.

Share this post


Link to post
Share on other sites

I received my JP heavy carrier and HP bolt yesterday, its amazing how fast I forgot the price when I had BCG in hand.  Such a high quality setup.  My barrel should be here sometime either the end of this month or beginning of next.  I emailed JP to inquire as to their recommendation for installing the PRS and what they suggested.  I got a very timely response basically recommending the A2 buffer tube with their heavy Gen II silent captured setup and just run the provided spacer.  I am still kicking that around, but I am still leaning on spending the coin to upgrade to the captured system.  I have never tried it before and I think this is the rifle that would benefit from that system. 

 

I have read enough reviews on the Superlative that I am now considering it, but I'm not there 100% yet.  I think it may come down to my decision on the handguard and how accessible the adjustments are. 

 

What die sets have you guys found that works best for the 260 in a semi auto platform.  I have been looking at the Redding FL size die with one of their nicer bullet seaters.  Its been some time since I purchased rifle dies and I feel like i'm out of the loop with options that are available today. 

Share this post


Link to post
Share on other sites

I just started shooting a jp lrp-07 in .260, man what a rifle.  300yd 6" diamonds in full value plus wind is nothing, almost boring in repetition.  Reloads 308 formed lapua brass with 130 bergers over h4350.  Velocity 2775.  Love it!

Share this post


Link to post
Share on other sites

For those who have gone with GAP or JP: how was your decision influenced to go with that versus LaRue and/or PWS?  I'm looking really hard at this right now after shooting one this weekend. 

Share this post


Link to post
Share on other sites

I didn't buy a factory rifle, but I will offer that whatever you decide, your decision should really take into consideration that the rifle have the XL gas system.  The +2" (longer than standard rifle length) gas port seems to be magic on either the 6.5 CM or the 260 Rem.  I know that JP has been selling theirs in that platform for quite a while, you will have to research the others as I am not that familiar with them. 

 

I recently received my barrel and gas tube from Proof Research, well, I ordered it from Stocky's Stock, one of their dealers. The Barrel looks great, now I just have to decide on a handguard.  I got stalled on my build because I gave into weakness and allowed another rifle to follow me home from a gun show and have been funneling funds into completing it, so my 260 got sidelined for a bit.  I'm still hopeful that I will have it complete with glass by the end of the year, but I want to build it right, so I'm not in a hurry. 

Share this post


Link to post
Share on other sites

I've gone with JP myself. Nothing against any of the others, but I feel like the other companies tend toward being a bit "tacti-cooler". I'm a competitive shooter and I feel that while JP certainly supports LE and MIL customers, they are very visible in the competition world in which I have been shooting. I know that a number of other companies have been around PRS-type matches, but I haven't. JP folk have always been very helpful when I've had questions. And, I also suspect it has something to do with coming from a 3-Gun background; JP has always been very visible in and around 3-Gun, so I feel more familiar with them and their products.

Share this post


Link to post
Share on other sites
Posted (edited)

Other than a quality barrel and obviously a good free floated handguard, is there any particular factor in the receivers themselves that make any better than others for building?  Like say for example if I pick up what is thought to be a cheaper AR10 platform in .308 and want to build a second upper as a precision 6.5CM, is there much holding it back from being very good if I use a good quality barrel (e.g. Criterion) and ammo to match?  (Assuming of course I put a good adjustable gas block on it, and of course have a good trigger in the lower.) 

Edited by yellowfin

Share this post


Link to post
Share on other sites

I think you will get a lot of different opinions on the receiver question.  It can become a Ford vs. Chevy Debate.  Obviously there are some Mercedes out there where you expect to get a lot when you pay a lot.  I have been using Aero Precision's stuff since they started.  Cheaper priced than most, but they were an aviation parts manufacturer with some high dollar equipment that simply got into the gun making business.  They used to have a lot more quality control methods that the standard receiver makers.  I have probably built in the neighborhood of 40-50 rifles on Aero's receivers and have never had a bad one yet, the machining is top notch.  They are a little more plain than some like.  These days there are a lot of very high end manufacturers that produce an outstanding product that anyone would be proud to have, but just expect to pay more, sometimes double the amount or more.  JP and Seekins Precision are a couple of those top tier manufacturers, I also really like Mega.  They also have a lot more cool features on the receivers.  for my AR10 build, I decided that I trusted the machining from Aero enough to build a quality rifle on their receivers, but I also wanted to cut costs somewhere, so that I could splurge in other areas like the JP BCG and the Proof Barrel.  I am doubting that I would see an accuracy advantage on the receivers as long as everything was in spec.  I think I had $270 into the set of Aero Large Frame Receivers.  I really wanted a set of Mega's for a long time, but at $600, I decided that the extra $330 went a long ways towards purchasing a high end barrel that I felt would make a greater improvement.  I recently helped one of my brothers build an AR10 on Aero receivers with a Criterion barrel in 308 and a JP BCG.  He is ecstatic over the build and it has worked very well for him. 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×