I plan on using a LMT MWS in precision rifle competitions and was wondering if anyone had advice for running a AR in LR competition. I'll be using a 26" 260 barrel with 1:8 twist and a Leupold MK6 3-18. I plan on shooting Burger 140 hybrids. Does anyone have pointers for stage planing with 20rd mags?
- Thread starter epaultmbt
- Start date
Did you get the barrel made already? If you use a rifle-length gas system, you're not doing yourself any favors with a 26" barrel.
I use a 22" barrel on my .260 Rem with RLGS, and am able to get 24" bolt gun velocities with most book loads. One bullet you might also consider is the Berger 130gr VLD. You will beat a lot of the 140's for drop and drift at 1000yds by running the 130gr VLD at 2800fps. You're pretty much limited to 2700fps with the 140's in a gas gun, unless you really tweak some things.
For mags, make sure you test your mag capacity with your COAL. The 20rd PMAGs are excellent in this regard, because they are curved. I use them exclusively in my .260 Rem AR built by GAP. If you have run-and-gun stages, a 20rd mag will usually get you through several stations, unless you're just really sucking or the target count is super high. Usually it's not because most matches are geared to bolt guns and putting in targets is hard/time-consuming for the organizers.
I would make sure you have gear that protects the mags from getting dirt in them. I've seen plenty of bolt guns, let alone self-loaders, go down in sandy conditions both here and overseas when the mags are inadvertently used to scoop up sand/dirt. Get down in different positions out in the field with your kit, and work out your mag changes and carry system so that you don't scoop up dirt. It can be a major time-killer for anyone in competition.
I use a 22" barrel on my .260 Rem with RLGS, and am able to get 24" bolt gun velocities with most book loads. One bullet you might also consider is the Berger 130gr VLD. You will beat a lot of the 140's for drop and drift at 1000yds by running the 130gr VLD at 2800fps. You're pretty much limited to 2700fps with the 140's in a gas gun, unless you really tweak some things.
For mags, make sure you test your mag capacity with your COAL. The 20rd PMAGs are excellent in this regard, because they are curved. I use them exclusively in my .260 Rem AR built by GAP. If you have run-and-gun stages, a 20rd mag will usually get you through several stations, unless you're just really sucking or the target count is super high. Usually it's not because most matches are geared to bolt guns and putting in targets is hard/time-consuming for the organizers.
I would make sure you have gear that protects the mags from getting dirt in them. I've seen plenty of bolt guns, let alone self-loaders, go down in sandy conditions both here and overseas when the mags are inadvertently used to scoop up sand/dirt. Get down in different positions out in the field with your kit, and work out your mag changes and carry system so that you don't scoop up dirt. It can be a major time-killer for anyone in competition.
Whats the story on the barrel? Where did you get the blank, who did the conversion for use in the mws?
I'm running my mws in precision comps in both 16" .308 and 20" 6.5cm variations. My 6.5 is only running about 2650 with 140 amax's but ive not had any trouble connecting with steel out to 960 yds. IMO, 26" in an ar is doing more harm than good in loss of maneuverability and portability.
The main thing you have to do is make sure your position is solid or you will wonder where those fliers are coming from. I've never had any reliability issues with my rifles and I've got easily 4-4.5k rounds down range in various configurations. I'm not one to clean often and this thing just keeps running, fwiw I'm running larue obr mags.
I'm running my mws in precision comps in both 16" .308 and 20" 6.5cm variations. My 6.5 is only running about 2650 with 140 amax's but ive not had any trouble connecting with steel out to 960 yds. IMO, 26" in an ar is doing more harm than good in loss of maneuverability and portability.
The main thing you have to do is make sure your position is solid or you will wonder where those fliers are coming from. I've never had any reliability issues with my rifles and I've got easily 4-4.5k rounds down range in various configurations. I'm not one to clean often and this thing just keeps running, fwiw I'm running larue obr mags.
I would think 22" would be more than enough... 26" is just a little out of control maybe??
Like some of the fellows here, I'm not sure that extra few inches is going to give you much advantage. I have been shooting a 24" AR in .260, and we are hammering a steel at almost 1100. Competent shooters, but nothing special. Shoots well in wind too. Surprised the hell out of me. I couldn't believe it was clanging. Wind blew my dope book across the road behind us. Next week I think we can get in a steel at 1200. If you do it, I'll be looking for pictures and a range report. Best.
LRRPF52,
Is there a reason I shouldn't use a 26" barrel with a rifle length gas system? Is it a reliability issue? I've been shooting 3gun and uspsa for some time and I'm looking for any gaming issues that may handy cap a gas gun. I've heard that some matches make everyone move on an open bolt due to safety issue with doctored bolt gun triggers. I read that if you set the mags put properly you'll be at bolt lock at the end of a string of fire and then reload on the move.
m1ajunkie, elfster1234,
26" because velocity is king for unknown distance and environments. If barrels weren't expensive and hard to find I'd shoot 243 as fast as I could. I'm prepared to lose maneuverability to gain points on target. With passive ranging and guessing at wind there's plenty of room for shooter err.
Is there a reason I shouldn't use a 26" barrel with a rifle length gas system? Is it a reliability issue? I've been shooting 3gun and uspsa for some time and I'm looking for any gaming issues that may handy cap a gas gun. I've heard that some matches make everyone move on an open bolt due to safety issue with doctored bolt gun triggers. I read that if you set the mags put properly you'll be at bolt lock at the end of a string of fire and then reload on the move.
m1ajunkie, elfster1234,
26" because velocity is king for unknown distance and environments. If barrels weren't expensive and hard to find I'd shoot 243 as fast as I could. I'm prepared to lose maneuverability to gain points on target. With passive ranging and guessing at wind there's plenty of room for shooter err.
JP offers their guns with 22" barrels and they don't seem to have any problems being competitive.
Sean
Sean
I for one have never seen an LMT with a 26"...... that's like bolt action barrel length type stuff and not totally sure on the gas system and how it would work... If you're absolutely dead set on long barrel, then I would say 24" tops but that is just my 2pcs..... also, I think it would just look uber strange having a LMT with that long of a barrel... i'm sure someone else on SH can give you much better advice on this topic than I, but my best guess would be 22" would be just about perfect.
That's going to be a heavy pig of a rifle, but not unlike something along the lines of AICS and the like. If that doesn't bother you, go for it.
I had a GAP built AR-10 with a 24" .260 barrel. It was an absolute pig. Like 20-something pounds. I couldn't dig the weight, so I sold it.
I handled an MWS last night. 16" CL barrel. It was a nice rifle, and I liked it in a 16", but a 24-26" .260 barrel would make the rifle god damn unmanageable.
I handled an MWS last night. 16" CL barrel. It was a nice rifle, and I liked it in a 16", but a 24-26" .260 barrel would make the rifle god damn unmanageable.
I run a Mega MKM in .260 with a 20" Lilja barrel. I agree that 26" is too long. I get almost full powder burn out of my 20. 22" would be max for me. I have been shooting the 123 and 142 SMK's in new Remington .260 brass with good results. I got a chance to talk with Bryan Litz who recommended the new 140 BTLR bullet. I have about 500 coming to work up a load. The .260 and AR10 platform were made for each other. I just love this rifle and shooting it is a dream. You get all the velocity you need to reach out past 1K accurately plus the high BC of the 6.5 bullets really helps with the wind. You'll love the LMT but I'd get the barrel shortened. It's just not necessary to have it so long in a gas gun.
The issue with a 26" gun and a Rifle-Length Gas System is that you have excessive dwell time. We use a lot of slow-burning powders in the .260 Rem, and the port location is pretty critical in that regard, because we don't want the accelerating gas dynamics to be past a certain point near the gas port. With a 26"/RLGS, you have longer dwell time once the projectile has passed the port, and the gas circuit is being pushed longer as a result.
The .260 Rem has very different gas dynamics than the .308, so port location and diameter need to be set by an experienced AR smith who has a strong handle on large frame AR's in alternate calibers. For competitive action shooting sports like USPSA-driven 3-gun, I wouldn't go any longer than a 20" gun personally, 22" max.
JP uses a lightweight contour barrel under the handguard, with a .936" gas block journal and heavy fore end, with the radiator fins attached to the barrel under the handguard. In an LMT, that 1.250" OD where it is pinched in place by the Monolithic Receiver Platform for about 4" makes even the 16" guns beastly little pigs that made me grimace when I picked one up for the first time.
If you were building a strictly bench or strong-supported (bipod/sticks/tripod) long stick for long-range shooting, you would want a 17" extended length gas tube/system and a 15" long handguard for the .260 Rem AR10. You would not be running & gunning with it unless you were 6'7"+/260lbs, and very developed with your overall musculature and physical conditioning. You would want heavy fluting of the barrel, a carbon fiber handguard, muzzle break, VTAC sling, and a PRS stock to counter the frontal weight.
My suggestion is to go with a 20" medium contour barrel with RLGS. If it's for gaming mostly, use an effective muzzle break. I personally would not choose the MRP for this application because of the significant barrel weight required by the pinch quick-change system, unless I had the new upper without quad rails, and a fluted barrel.
I agree with Danco411: The .260 Rem and AR10 were built for each other. You get good barrel life if you keep your loads under 2900fps with certain powders, trajectory and drift are laser-like, recoil is less than a .308, and it's not fun to shoot within 700yds on IPSC sils.
I used to have a 6.5 Grendel with a 24 inch tube. When I got a 20 inch tube, I was stunned at how much more maneuverable the rifle was. I don't shoot USPSA, but shoot a lot of practical/precision rifle, and found that swinging between targets was dramatically easier. Of course, it is easy to see how the hotter barrel makes it easier to shoot through various ports, move from side to side on barricades and so on. Knowing that, Imwould think that 20 inch to 22 inch max would be the way to go. I still have rifles with long tubes for various applications, but if Imwere buildings 260 gas gun, I would use a 22 inch barrel.
It is worth considering what you are trying to accomplish with your rifle. If all you need to do is tag steel, my Grendel's 123 scenario doesn't go transonic until 1400 yards depending on atmospheric/environmental factors. if you have to knock the targets down then the increase in power and recoil of the 260 would be a worthwhile trade.
Most of the local matches here only go out to 550 yards, and it seems to me that the Grendel is made for those distances..the low recoil is a big advantage over a full sized cartridge...but we only have to strike steel, not knock it down.
It is worth considering what you are trying to accomplish with your rifle. If all you need to do is tag steel, my Grendel's 123 scenario doesn't go transonic until 1400 yards depending on atmospheric/environmental factors. if you have to knock the targets down then the increase in power and recoil of the 260 would be a worthwhile trade.
Most of the local matches here only go out to 550 yards, and it seems to me that the Grendel is made for those distances..the low recoil is a big advantage over a full sized cartridge...but we only have to strike steel, not knock it down.
I was thinking the Grendel in the back of my mind responding to this as well. When it comes to position shooting, a 16" Grendel can't really be beat. Mine also flattens my 12" poppers at 300yds with just the 90gr TNT load from AA, and there is a clear impact of steel plates at 600yds as well with the 123gr A-MAX, Scenar, SMK, & Nosler CC.
An 18" Grendel makes a great 3-gun carbine if there are a lot of stages with more traditional rifleman skills, versus heavy close-range hose sessions where a lower-recoiling 5.56 will give you better splits.
If you go the JP racegun approach anyway, you will make a Grendel that feels recoilless with the Silent Captured Spring, adjustable gas block, muzzle break, & maybe the new Lo-mass bolt carrier that has the black QPQ stainless construction/surface treatment. Run the Wolf 120gr MPT, which usually goes for $13 per box, and hose away. You'll not find anything close to that price in .260 Rem.
You can also use 25rd mags. Just make sure your ejector face is radiused to deal with feeding, and the gun is built well by someone that knows what they're doing. Might as well go JP for a 3-gun Grendel.
An 18" Grendel makes a great 3-gun carbine if there are a lot of stages with more traditional rifleman skills, versus heavy close-range hose sessions where a lower-recoiling 5.56 will give you better splits.
If you go the JP racegun approach anyway, you will make a Grendel that feels recoilless with the Silent Captured Spring, adjustable gas block, muzzle break, & maybe the new Lo-mass bolt carrier that has the black QPQ stainless construction/surface treatment. Run the Wolf 120gr MPT, which usually goes for $13 per box, and hose away. You'll not find anything close to that price in .260 Rem.
You can also use 25rd mags. Just make sure your ejector face is radiused to deal with feeding, and the gun is built well by someone that knows what they're doing. Might as well go JP for a 3-gun Grendel.
Thank you for taking the time to respond.
I've been shooting 3gun and USPSA since 2004 and my gear and gaming is pretty well set. I'm a TO and non magnified shooter. I considered some heavy metal with MWS and a 13.5"/pinned 16" but I refuse to build a pump SG or gear up a 45ACP. I wish they would just give more points on paper for 7.62 in TO. I'd really like to shoot a rifle caliber in those games.
I've got thousands of rds on several SR25/AR10 platforms and I've had the LMT MWS for 3 years and have a few barrels for it. I've got 9 LR matches under my belt using a LMT 18 SS barrel. 7.62x51 (M118LR) is out gunned at these matches. I considered something in 6mm but settled for 6.5mm understanding that I would be dealing with more recoil. These matches have MV limits of 3100fps ish and I intend on shooting bullets as fast as reasonably possible.
Where I have the most difficulty is judging wind on ranges that I've never shot in places I've never been, and passive range estimation. If laser RF are allowed it changes the game a bit but makes it a bit more expensive to play. I'm capable of mil. to the tenth but with M118LR often that's a first round miss and points lost on target. I run SF MBs on all my guns and my new barrel will have one as well. I thank every one for the input. I'm going to start with a 26" and cut from there. I'm young and move fast so I shouldn't lose much due to weight or length. Plus I've never seen any of these match ask for much movement. If they do good. I've always said "thank god I'm fast, because I can't shoot for shit".
I've read that several major matches have rules about moving with the bolt open, and was wondering if that was still the case. If so how do you plan around that with a gas gun? If not awesome. It makes sense to safe and move works for the rifles being used in 3gun and that sport has been more fast pace then any LR match I've shot. Hell in 3gun you can move on fire just don't break the 180.
R/S
I've been shooting 3gun and USPSA since 2004 and my gear and gaming is pretty well set. I'm a TO and non magnified shooter. I considered some heavy metal with MWS and a 13.5"/pinned 16" but I refuse to build a pump SG or gear up a 45ACP. I wish they would just give more points on paper for 7.62 in TO. I'd really like to shoot a rifle caliber in those games.
I've got thousands of rds on several SR25/AR10 platforms and I've had the LMT MWS for 3 years and have a few barrels for it. I've got 9 LR matches under my belt using a LMT 18 SS barrel. 7.62x51 (M118LR) is out gunned at these matches. I considered something in 6mm but settled for 6.5mm understanding that I would be dealing with more recoil. These matches have MV limits of 3100fps ish and I intend on shooting bullets as fast as reasonably possible.
Where I have the most difficulty is judging wind on ranges that I've never shot in places I've never been, and passive range estimation. If laser RF are allowed it changes the game a bit but makes it a bit more expensive to play. I'm capable of mil. to the tenth but with M118LR often that's a first round miss and points lost on target. I run SF MBs on all my guns and my new barrel will have one as well. I thank every one for the input. I'm going to start with a 26" and cut from there. I'm young and move fast so I shouldn't lose much due to weight or length. Plus I've never seen any of these match ask for much movement. If they do good. I've always said "thank god I'm fast, because I can't shoot for shit".
I've read that several major matches have rules about moving with the bolt open, and was wondering if that was still the case. If so how do you plan around that with a gas gun? If not awesome. It makes sense to safe and move works for the rifles being used in 3gun and that sport has been more fast pace then any LR match I've shot. Hell in 3gun you can move on fire just don't break the 180.
R/S
A buddy of mine shoots a jp .260 and he is very competitive...just like any gas gun -not as forgiving as a bolt gun.
The LMT barrels are all now 1:9 twist. They don't make 1:8 any more. Is this going to be a problem running 130gr loads?
I'm looking at picking up an LM8MWS, and am wondering if the 1:9 will still work decently.
I'm looking at picking up an LM8MWS, and am wondering if the 1:9 will still work decently.
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