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What weight buffers are you guys finding to work well with the 6.5 grendel.
Only reason I am asking as I built one that I gave to a friend of mine that was very easy to set up.
My current build was not so easy, I took the buffer out and it only comes in at a little under 3 ozs, seems a little light.
Do not know the weight on the one in the first build, both were purchased from AP though.
I might have balled something up in the ordering, dont know.
Both guns running SLR blocks.
Thanks, Greg
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Got the standard jp silent captured spring and odin works adjustable tuned to my loads on a 24", it was really aggressive with the hornady black even at the lowest bolt hold open setting denting the case necks pretty bad.
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I'm using an Armaspec Stealth Captured Spring (H2 weight) with my 18" MLGS barrel and my action cycles well and I don't even notice the recoil. You can buy a kit of tungsten weights and experiment without buying a new buffer. There are however some barrels out there with gas ports which are larger than Alexander's spec and they may still need an adjustable gas block or gas key to tame them.
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blackholegun Wrote:Both guns running SLR blocks.
Greg,
If your SLR blocks are adjustable then that's all the tuning you need. You can have any weight buffer and spring in there. Dial back the gas until it just locks back on last round for that weight of buffer and spring, then one more click to be sure. A heavier buffer and BCG carries with it more momentum to load the next round so a H2 is a good compromise.
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ClutchAutomatic Wrote:Got the standard jp silent captured spring and odin works adjustable tuned to my loads on a 24", it was really aggressive with the hornady black even at the lowest bolt hold open setting denting the case necks pretty bad.
Clutch, the length of the Grendel case results in the case mouth impacting the shell deflector and denting the mouth. 300 blackout rounds do the same thing. .223/5.56 cases are longer, so they get a dent in the side of the case. I don't think you can adjust that out with tuning buffers, recoil springs, or gas blocks. Trim a coil or two off of your ejector spring or just put a piece of fuzzy velcro on the shell deflector to stop the case mouth dents.
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+1, although what I am referring to is the 'aggressive' ejection which implies too much gas.
Drillboss is right about the case denting. I trimmed the length of coil that protrudes past the hole when uncompressed and this solved the denting problem.
Clutch, on the clock-face with 12 O'Clock being the where the barrel is pointing where do your cases eject?
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Klem Wrote:+1, although what I am referring to is the 'aggressive' ejection which implies too much gas.
Drillboss is right about the case denting. I trimmed the length of coil that protrudes past the hole when uncompressed and this solved the denting problem.
Clutch, on the clock-face with 12 O'Clock being the where the barrel is pointing where do your cases eject?
Yeah I might put some fuzzy velcro on the deflector, hard to tell which way it is ejecting because I am currently only shooting indoors where its smacking off the wall. With my handloads I have them dialed down to where the case mouth isn't getting dented and still shooting sub half moa 5 shot groups.
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The dented case mouth really isn't that big of an issue, resizing opens it right back up. I just don't like the brass marks that it leave on my shell deflector. Trimming the spring will eliminate it.
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The first build I did was with an 18" Faxon gunner barrel and a gas system described as "mid".
I know that one had a standard mil spec buffer.
The current build has an 18 " BA fluted barrel with a rifle length gas system, finding out they are all unique.
Both were built on a carebine length buffer system.
I have a 223 wylde upper I am planning on running with this lower.
So I think I will keep the light buffer for that combo and purchase a heavier one for the 6.5.
H or H2, any suggestions would be appreciated
Thanks. Greg
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blackholegun Wrote:The first build I did was with an 18" Faxon gunner barrel and a gas system described as "mid".
I know that one had a standard mil spec buffer.
The current build has an 18 " BA fluted barrel with a rifle length gas system, finding out they are all unique.
Both were built on a carebine length buffer system.
I have a 223 wylde upper I am planning on running with this lower.
So I think I will keep the light buffer for that combo and purchase a heavier one for the 6.5.
H or H2, any suggestions would be appreciated
Thanks. Greg
Spikes T2 or Kaw valley, along with the JP centerless spring (carbine length). Smooths it out nicely, not a lot of money...
my $0.02.
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blackholegun Wrote:The first build I did was with an 18" Faxon gunner barrel and a gas system described as "mid".
I know that one had a standard mil spec buffer.
The current build has an 18 " BA fluted barrel with a rifle length gas system, finding out they are all unique.
Both were built on a carebine length buffer system.
I have a 223 wylde upper I am planning on running with this lower.
So I think I will keep the light buffer for that combo and purchase a heavier one for the 6.5.
H or H2, any suggestions would be appreciated
Thanks. Greg
It all depends on port diameter and the load you're shooting, as well as the condition of the BCG, chamber, and recoil spring.
The Grendel was engineered to be a drop-in solution for existing AR15 lowers, but many barrels in the after-market have used different gas port diameters.
The Grendel gas ports actually seem to correspond with 5.56 gas port diameters at the different locations.
Buffer weights are primarily for countering carrier bounce on automatic-capable rifles, with a secondary function as rate reducers.
The buffer style we currently use was actually meant as a rate reducer when the Army switched to ball powders in the AR15 in the early 1960s, even though the rifle was engineered around tiny extruded powders like 8208M.
Depending on what load you shoot, your port pressure will be quite different, so it really helps to nail down what load range you primarily want to feed the system.
The extremes of that with 6.5 Grendel are 85gr on the low end for hand loads, followed by 90gr TNT factory ammo from Federal, with 130gr on the high end of factory ammo, and even heavier for hand loads.
Some ways to deal with this are adjustable gas. The easiest adjustable gas system I've seen so far is the Bootleg Adjustable Gas Carrier, which I have.
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LRRPF52 Wrote:It all depends on port diameter and the load you're shooting, as well as the condition of the BCG, chamber, and recoil spring.
The Grendel was engineered to be a drop-in solution for existing AR15 lowers, but many barrels in the after-market have used different gas port diameters.
The Grendel gas ports actually seem to correspond with 5.56 gas port diameters at the different locations.
Buffer weights are primarily for countering carrier bounce on automatic-capable rifles, with a secondary function as rate reducers.
The buffer style we currently use was actually meant as a rate reducer when the Army switched to ball powders in the AR15 in the early 1960s, even though the rifle was engineered around tiny extruded powders like 8208M.
Depending on what load you shoot, your port pressure will be quite different, so it really helps to nail down what load range you primarily want to feed the system.
The extremes of that with 6.5 Grendel are 85gr on the low end for hand loads, followed by 90gr TNT factory ammo from Federal, with 130gr on the high end of factory ammo, and even heavier for hand loads.
Some ways to deal with this are adjustable gas. The easiest adjustable gas system I've seen so far is the Bootleg Adjustable Gas Carrier, which I have.
I am running SLR adjustable gas blocks on all of my builds, 2 6.5 grendel's and one 6.5 Creedmoor.
My current build is a little finicky it seems, all of the parts are new.
AP BCG
AP UPPER AND LOOWER
BA 18" FLUTED BARREL Rifle length gas
ELANDER 10 ROUND MAGS
Just a fussy combo I guess.
Tried shooting it again last and had a couple FTF.
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02-08-2018, 02:36 AM
(This post was last modified: 02-08-2018, 02:42 AM by VASCAR2.)
If your getting failure to feed try putting a radius on the ejector. On larger case heads like the 6.5 Grendel the square edge on the ejector can impede the case head from seating in the face of the bolt and causing a failure to feed. The bullet nose may fail to go from the mag and up the feed ramps stopping prior to completely seating in the chamber. Putting a radius on the edge of the ejector can’t hurt and is worth trying if your having failure to feed.
http://bulletin.accurateshooter.com/2014...artridges/
Here is a thread where a 6.5 Grendel shooter was experiencing failure to feed which might be worth reading.
https://www.ar15.com/forums/AR-15/6-5-Gr...21-722238/
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blackholegun Wrote:I am running SLR adjustable gas blocks on all of my builds, 2 6.5 grendel's and one 6.5 Creedmoor.
My current build is a little finicky it seems, all of the parts are new.
AP BCG
AP UPPER AND LOOWER
BA 18" FLUTED BARREL Rifle length gas
ELANDER 10 ROUND MAGS
Just a fussy combo I guess.
Tried shooting it again last and had a couple FTF. What ammo?
18" RLGS runs best with slow-burning powders and heavier bullets, at least 120gr or more.
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6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
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American Eagle 120 grain open tip match, it is the only round I can purchase locally.
I do not have the equipment to do handloads.
I did order a Spikes T2 buffer, will have to see if that helps
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blackholegun Wrote:American Eagle 120 grain open tip match, it is the only round I can purchase locally.
I do not have the equipment to do handloads.
I did order a Spikes T2 buffer, will have to see if that helps
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Yeah, I just ordered 10 boxes of Hornady black.
Also received my T2 buffer, Primary Arms shipping is amazingly fast.
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Cool. After trying that combo, get the centerless spring, gets rid of most all of the sproing!
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blackholegun Wrote:American Eagle 120 grain open tip match, it is the only round I can purchase locally.
I do not have the equipment to do handloads.
I did order a Spikes T2 buffer, will have to see if that helps
What's your gas port diameter?
You might need the port opened since you have 18" RLGS.
Most 18" Grendels are MLGS, which is gassed pretty hard, but some have a more ideal Intermediate Length Gas System.
Precision Firearms introduced ILGS many years ago, and I think Odin Works uses it as well.
If your port is too small, with that reduced plug dwell time, it can cause short-stroking malfunctions.
Does the bolt ride over the base of the next cartridge when you see the malfunctions?
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Well, shit, the heavier buffer and the JP spring did not help as I would hoped it would.
I did the one round in the mag and adjust the gas block until the bolt holds open, then one more turn open.
It works fine as a single shot.
Can not even get to the second or sometimes the third round without it not ejecting completely and jamming with more than one round in the mag.
Even tried another ELANDER same shit.
This was with the American Eagle 120 grain rounds again as that is all I have currently.
I do not know the gas port diameter on the barrel, will have to take it apart and measure it I guess.
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