New Rifle from LaRue - the MRGG-S 6.5 Creedmoor
- Thread starter RedBreast21
- Start date
I wasn't suggesting that it was the weight per se, but that the 140 class of bullets doesn't necessarily play as well in Larue's barrels (to the extent the 6.5 and .260 barrels are the same or similar), and that the 130 AR hybrids were found - by multiple users - to be better performers.
I'll stand by my assertion that Hornady bullets are not as good as the other three in terms of consistency of quality.
Goes to show you weapon to weapon things can be different. My 18” LaRue 6.5 loves the Hornady 147 hand loads but hates the 130 Berger’s. While most of my bolt guns shot the 130 Berger’s into
One hole
One hole
I just got back from the range doing load development with some very nice results I'll update this thread soon as I get home with data and pics.
Started load development today and had some promising results, now that I have control over the neck tension over factory offerings the groups are very consistent with no unprovoked Flyers.
Only Flyer I had today was with the last 5rd group 40.9grs H4350, I think it was a case of Buck Fever.
I'll repeat loads 40.2, 40.4, 40.6 and 40.9
I haven't started to see any signs of over pressure so I'll keep working my way up.
Also had a little somethin arrive today to assist with the load development
Only Flyer I had today was with the last 5rd group 40.9grs H4350, I think it was a case of Buck Fever.
I'll repeat loads 40.2, 40.4, 40.6 and 40.9
I haven't started to see any signs of over pressure so I'll keep working my way up.
Also had a little somethin arrive today to assist with the load development
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The LT MRGG Rifles have a 20" Barrel with a 1-7.5 Twist, it's going to favor the heavier Projectiles.
Everyone I know who Shoots LT Rifles in .260 Rem all get better performance with Projectiles in the 130gr - 139gr.
His 6.5CM barrels prefer the 140's and up range of Projectiles.
Larue shoots the 6.5CM MRGG Proof Targets with Hornady 140gr ELD Match Factory Ammo, and I could be wrong but if I was shooting Proof Groups for each of my rifles I'd definitely shoot the most Accurate Ammo to make my rifles look good.
Sir, this is Mark LaRue we're talking about. One should not assume things to be rational or optimal.
Thank you @Bigjake83 for posting your results. I would love to know what the differences are between the MRGG and PredatOBR rifles. Other than the FDE color and cool spiral fluted barrels.
My tOBRs have become my favorite rifles.
My tOBRs have become my favorite rifles.
The only difference that you can't visually see is that the MRGG Barrels have a smaller diameter Barrel Extension with a very, very slight taper.
If there are any other MRGG owners wanting different calibers/length I'll start keeping a few on hand in .308, 6.5CM and maybe .260
As the rifle sits now, it's a consistent .65-.75 MOA rifle with Hornady 140 ELD Match Ammo.
I'm Very interested in seeing how a Custom Bartlein performs in the MRGG.
Current Set-up.
I'm Very interested in seeing how a Custom Bartlein performs in the MRGG.
Current Set-up.
BigJake83, I have a 6.5 Larue MRGG identical to yours. I just put a suppressor on it ( deadair sandman X). Obviously it's way over gassed now. I can't find anything on adjusting these gas blocks. Obviously you turn one way or the other to adjust. I was wondering if you could tell me where your's is adjusted? I'm assuming turn all the way (which way?) then work your way to the correct setting. Any help would be appreciated. Thank you
I can't tell you where my gas setting is at because it doesn't have click adjustments, it's an infinite fine tunable adjustable gas block.
Turn in to reduce gas flow, back it out to increase gas.
Turn it all the way in and fire one round at a time while backing the adjustment screw out a 1/2 turn after each shot, checking for the BCG to lock to the rear on an empty mag. Once it reliably locks to the rear you can fine tune it to your preference, I set mine up so the ejection pattern is close to or at 3 o'clock.
If you're suppressor is NOT a flow through design I would Swap the H2 for a H3 Buffer as well.
Hope this helps.
Jake.
PS...
I'm running a JP H3 SCS in mine as she's a Smooth Criminal.
Paul Ross has also just finished up a 22" Bartlein 6.5CM Barrel for mine, will post Groups and Data on my next Range Day.
Turn in to reduce gas flow, back it out to increase gas.
Turn it all the way in and fire one round at a time while backing the adjustment screw out a 1/2 turn after each shot, checking for the BCG to lock to the rear on an empty mag. Once it reliably locks to the rear you can fine tune it to your preference, I set mine up so the ejection pattern is close to or at 3 o'clock.
If you're suppressor is NOT a flow through design I would Swap the H2 for a H3 Buffer as well.
Hope this helps.
Jake.
PS...
I'm running a JP H3 SCS in mine as she's a Smooth Criminal.
Paul Ross has also just finished up a 22" Bartlein 6.5CM Barrel for mine, will post Groups and Data on my next Range Day.
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Thank you for responding! Took it out today and had nothing but issues once I started adjusting.. Half way through the session my bolt catch broke off.... Then it was double feeding.. Never stopped ejecting brass to the 1'oclock position? It seemed to just eject weaker at the 1'oclock as I adjusted, then double feed? I think I'm going to have to go the JP route like you. Not a good range day. I'm VERY interested to hear how your Paul Ross Bartlein turns out!! Please post pics!! Any more advice would be appreciated. Thank you sir..
Holy smokes . . . I've been doing this for awhile and I can't say that I've ever heard of this happening. I had a defective bolt catch from LMT once, but it didn't BREAK OFF.
Did the pin shear or did the catch itself break? We have to see pictures of this.
That’s usually the sign of an over gassed large frame AR unless the part is defective
I have an OBR with two positions block. I did not know LaRue switched to adjustable design
Wow. It broke in pieces. I concur with the other poster. This strongly suggests that the rifle is way (way, way) overgassed. In my adventures with getting a silencer/load setup to work in all configurations (.260 suppressed/unsuppressed, .308 suppressed, unsuppressed) with my PredatOBR, I shot a lot of slow motion video and it became clear that you can beat up that rifle if you're not careful. I'd start by getting a Slash's XL Heavy buffer, and make sure you're NOT using an extra power spring (because the return velocity on an XP spring is that much higher).
Just to clarify by me switching to the JP SCS it didn't alleviate any issues, I actually haven't had any issues to date. The JP SCS just made it cycle a bit smoother my rifle was still running 100% reliable with the original buffering system.
What ammo and suppressor are you using?
Also just so all other LaRue owners are aware I recently purchased a Brand New Old Stock PredatAR that had a out of spec handguard that was leaning to the left side.
when I sent it back to Larue for warranty and repair, I was told that they're no longer able to warranty the older models like the OBR and PredatAR if it has anything to do with the OBR or tAR Handguards or upper receiver because they have none left to send out for replacements.
I was offered a complete Stealth Upper as a replacement, but the new old stock tAR was bought as collector's piece so a stealth upper would be pointless. Three day later they found one hiding in the back somewhere.
I also asked if they could switch it out for a OBR or PredatOBR upper and I'd happily pay the difference, this is when I was told they definitely have NO OBR part left over and the PredatOBR was soon to fallow that same fate.
when I sent it back to Larue for warranty and repair, I was told that they're no longer able to warranty the older models like the OBR and PredatAR if it has anything to do with the OBR or tAR Handguards or upper receiver because they have none left to send out for replacements.
I was offered a complete Stealth Upper as a replacement, but the new old stock tAR was bought as collector's piece so a stealth upper would be pointless. Three day later they found one hiding in the back somewhere.
I also asked if they could switch it out for a OBR or PredatOBR upper and I'd happily pay the difference, this is when I was told they definitely have NO OBR part left over and the PredatOBR was soon to fallow that same fate.
I would look at the distance between the bolt and the bolt catch at full pull-back of the charging handle. Too much distance and the BCG gains too much momentum when it engages the catch. Over-gas is more of a problem with bumper bounce when using solid or 308 short carbine buffers, reciprocating weight buffers kill most of that bounce.
Thank you everyone for your help, very MUCH appreciated! I found mine groups best with Hornady 147 eld, So that's what I've been using. My suppressor is the new 30 cal Dead air Sandman X. I actually sent Larue an email at the same time I posted on here. I just got their response which I will post below. They were actually kind enough to offer to send me out a new bolt catch.
Good morning, Matt.
Sorry for the delay. To close the gas block on the MRGG you would need to turn the nut clockwise with a 3/16ths socket and counter clockwise to close it. We can't say where exactly your tuning will land with that particular can given that our rifles are tuned for the Tranquilo suppressors. You will have to shoot, unload/clear, adjust and repeat till you have the desired ejection pattern. Also ensuring you still have enough gas to lock the bolt back on the last round.
If you are unable to close off the excess gas while still getting lock back, then you'll most likely have to start diagnosing the buffer system.
Can give me a good shipping address? I'll see what I can do about getting you set up with a new bolt catch.
So to close it you turn it clockwise, but to close it you turn it counter clockwise? I'm assuming the second "close" was meant to be "open." I can't imagine even the nuttiest of engineers would make it so a counter-clockwise turn would close something - even Mark.
No its definitely clockwise to turn the gas down/off. If I turn mine in all the way in the BCG doesn't even move with a can on.
I LOL'd when I read that as well.
I was leaning with 'righty tighty' and 'lefty loosey'
