14.5" Grendel

[Chrazy-Chris]

Any of you guys ever do a 14.5" Grendel? I've been wanting to build one for awhile now to run suppressed with a pinned FH. I have a specwar762 which is a bit of a beast when you throw it on. For this use, I'm thinking a mid-length gas system with adjustable GB would be nice. Any issues with dwell time for unsuppressed? Are there any 14 or 14.5" barrels available? (my FH is 2" long)

[rabiddawg]

I believe Lilja makes one.

Just went and looked. Lilja has 11.5" and 12.875". No 14's

[41bear]

X-Caliber will build you any length you want up to 24" for up to about $450.

http://www.x-caliber.net/custom-ar-barrel

[js8588]

I know I'm new here and I hate to be "that guy" but please, don't do that. Don't use a barrel that's going to ballistically handicap a great round. The shortest I would (will) go on a Grendel is 18 inches. I feel the same about my 556s too. Even 16 seems too short. Then again, I'm 6'2 and 205lbs. Longer barrels fit me fine.

[Bigs28]

Short barrel 6.5 grendel have phenomenal ballistics. Not everyone has thousand yard ranges. Precision firearms will do short barrels as well.

[kmon]

there is a lt to be said for a shorter barreled Grendel or anything else to a point. If you doubt the effectiveness of a 14.5 barrel look at he 16 inch barred data on Hornady's website. From what I consider a very good source that data is actually from a 14.5 inch barrel with a flash hider making it 16 inch over all.

Almost all barrels are a compromise for length, just about every cartridge out there can benefit some from a longer barrel up to a point where expansion ratio and bullet friction and mass in the barrel overcome the push provided by the burned powder. A 22 Short, Long and Long rifle are good examples of the latter. Standard velocity 22LR is actually slowing down in a 24 inch tube.

Guns, cartridge selection and loads for them are all a trade off.

[Chrazy-Chris]

I know I'm new here and I hate to be "that guy" but please, don't do that. Don't use a barrel that's going to ballistically handicap a great round. The shortest I would (will) go on a Grendel is 18 inches. I feel the same about my 556s too. Even 16 seems too short. Then again, I'm 6'2 and 205lbs. Longer barrels fit me fine.

I've done a LOT of research into this (mostly because I really don't need to drop money on another rifle at this point in my life so the next best thing I can do is go full nerd on the research for one) and I went through the following steps to choose this setup:

-I have several AR's but none of them are very comfortable to carry with my suppressor - a 9" 24oz tank of a suppressor. 14 or 14.5" is as short as I want to go w/ pinned FH (don't want to do paperwork or carry a "pistol" for hunting).
-I don't have the money to build an AR-10 and an added plus, I can use an AR-15 lower I already have built with a nicely broken-in SSA and nice stock/grip/enhanced buffer spring... Must -be a cartridge that fits in a standard AR-15.
-I want the ability to kill deer with it @400yrds. I used ft-lbs of energy and considered velocities required to expand hunting rounds. The max range I would take on a deer is 400yrds.

With these parameters, I calculated the ballistics data for several different loads with recorded 14.5" barrel velocities from 5.56, 300blk, 7.62x39, 6.8SPC, and 6.5 Grendel. The Grendel beat out all the other cartridges @400yrds with the most energy on target while still having the required velocity to expand the bullet on impact. An added plus was the lower wind drift.

The Grendel was the clear choice for me to build in this setup. Additionally, I already have a 20" Grendel I use for shooting steal out to 1k. Box checked. With my suppressor, a 14" barrel turns into a (heavy) 23" barrel. I'm 6'2" 185lbs and consider myself to be in great shape. Carrying a 20" barrel plus suppressor is still just too unwieldy for spot and stalk. I spent the money for this can and I want to use it in a platform that I actually carry, rather than just on pistol range toys or benchrest guns. Finally, this is America and I can do what I want (within the letter of the law).

ETA: For factory 123SST with advertised 2350fps MV from 16" barrel (described above from Kmon as a pinned 14.5") @3000' Elevation (my hunting grounds):
@400yrds- Velocity: 1804fps; Energy: 889ft lbs, Holdover: 3.0mils, 10mph wind drift: .9mils

For comparison's sake- with the 18" you'd recommend, figuring a MV of 2435fps (extrapolated the difference in advertised MV between 14.5" and 24" for a loss of 24fps/in):
@400yrds- Velocity: 1877fps; Energy: 962ft lbs, Holdover: 2.7mils, 10mph wind drift: .8mils

I don't think Mr. Mule Deer will know the difference but I sure will when carrying the gun up and down the canyons.

[pajasonc]

I've done a LOT of research into this (mostly because I really don't need to drop money on another rifle at this point in my life so the next best thing I can do is go full nerd on the research for one) and I went through the following steps to choose this setup:

-I have several AR's but none of them are very comfortable to carry with my suppressor - a 9" 24oz tank of a suppressor. 14 or 14.5" is as short as I want to go w/ pinned FH (don't want to do paperwork or carry a "pistol" for hunting).
-I don't have the money to build an AR-10 and an added plus, I can use an AR-15 lower I already have built with a nicely broken-in SSA and nice stock/grip/enhanced buffer spring... Must -be a cartridge that fits in a standard AR-15.
-I want the ability to kill deer with it @400yrds. I used ft-lbs of energy and considered velocities required to expand hunting rounds. The max range I would take on a deer is 400yrds.

With these parameters, I calculated the ballistics data for several different loads with recorded 14.5" barrel velocities from 5.56, 300blk, 7.62x39, 6.8SPC, and 6.5 Grendel. The Grendel beat out all the other cartridges @400yrds with the most energy on target while still having the required velocity to expand the bullet on impact. An added plus was the lower wind drift.

The Grendel was the clear choice for me to build in this setup. Additionally, I already have a 20" Grendel I use for shooting steal out to 1k. Box checked. With my suppressor, a 14" barrel turns into a (heavy) 23" barrel. I'm 6'2" 185lbs and consider myself to be in great shape. Carrying a 20" barrel plus suppressor is still just too unwieldy for spot and stalk. I spent the money for this can and I want to use it in a platform that I actually carry, rather than just on pistol range toys or benchrest guns. Finally, this is America and I can do what I want (within the letter of the law).

ETA: For factory 123SST with advertised 2350fps MV from 16" barrel (described above from Kmon as a pinned 14.5") @3000' Elevation (my hunting grounds):
@400yrds- Velocity: 1804fps; Energy: 889ft lbs, Holdover: 3.0mils, 10mph wind drift: .9mils

For comparison's sake- with the 18" you'd recommend, figuring a MV of 2435fps (extrapolated the difference in advertised MV between 14.5" and 24" for a loss of 24fps/in):
@400yrds- Velocity: 1877fps; Energy: 962ft lbs, Holdover: 2.7mils, 10mph wind drift: .8mils

I don't think Mr. Mule Deer will know the difference but I sure will when carrying the gun up and down the canyons.

I don't think you are going to get much expansion with the sst at 400 yards unless your hunting at high elevations. 1800 is the min but they won't expand much if you don't hit bone. Also most 18" are going to be in the 2450 to 2500 range(not much difference but still some difference)

[LRRPF52]

I know I'm new here and I hate to be "that guy" but please, don't do that. Don't use a barrel that's going to ballistically handicap a great round. The shortest I would (will) go on a Grendel is 18 inches. I feel the same about my 556s too. Even 16 seems too short. Then again, I'm 6'2 and 205lbs. Longer barrels fit me fine.

Optimum barrel length for 5.56 for a work gun is probably 12.5". BCs are so low that you bleed energy really fast, to the point that longer barrels just don't give you the performance you think they would.

Within 200yds, 5.56 is a great system, still has respectable retained energy, high hit probability.

For 6.5 Grendel, a 10.5" has more energy at the muzzle than a 20" hot-loaded 5.56 NATO, and it only separates from there in the Grendel's favor as the distance increases.

There isn't a lot of practical difference between a 14.5" Grendel and a 16" Grendel. You're in the 2350-2440fps range with 123gr factory ammo.

If I cherry-pick the velocities with 14.5" mv vs. 16" mv, using 2350fps vs. 2440fps, the numbers still are very close, .1 mils drift difference across supersonic reach.

Using staged G7 BC of .247 for the 123gr ELD-M at 2350fps, we're looking at 475yds of expansion for the 14.5" at sea level, 59˚, supersonic to 850yds. Spin stability with 1/7.5" twist will keep it on-target past that.

For the 16" at 2440fps, expansion is out to 525yds, supersonic to 925yds with 123gr ELD-M.

Your 200yd hunting zero keeps both within a 10" vital zone out to 225yds.

Impact energy for both at 225yds:

14.5" 1076ft-lbs
16.0" 1167ft-bs

Where I'm at, the numbers change drastically because of altitude/air density, so that both are supersonic to 1100 and 1150yds with the 123gr ELD-M at 2350 and 2440fps.

For a hunter looking for a compact package that also does more than you would think as a fun target-shooting carbine, they will surprise you.

Load them with the 129gr ABLR, and the expansion numbers will exceed most people's hunting distances by 2-3x easily.

[LRRPF52]

The 16" data on Hornady's site is in fact a 14.5" AA Grendel with a pinned muzzle device, confirmed by Hornady tech support.

Use .462 G1 BC for your 123gr SST calculations within 600yds.

If you hand load for the 14.5", you can probably get 2450fps easily with CFE223.

You can also load the 129gr ABLR.

As pajasonc stated, 18" Grendel with a 123gr has typically been in the 2457-2511fps range for me using several different factory 120-123gr loads.

You will still get expansion on soft tissue down to 1800fps with the 123gr SST, especially with Grendel twist rates.

[Kilco]

I know I'm new here and I hate to be "that guy" but please, don't do that. Don't use a barrel that's going to ballistically handicap a great round. The shortest I would (will) go on a Grendel is 18 inches. I feel the same about my 556s too. Even 16 seems too short. Then again, I'm 6'2 and 205lbs. Longer barrels fit me fine.

Couldn't disagree more. I use a 16" Grendel and the performance I've gotten rivals that of my 20" 308. Run the numbers and you will see even a 12.5" Grendel with the right ammo is a very viable hunting setup for much further than most people would ever need.

[Troutguide]

I want an under 200yd hog gun for mostly woods stalking. A 12" Grr will do me just fine, and if I ever get the cash for a can it will still be a short light gun. I have a 20" hb bolt grendel for the long stuff. Lots of viable configurations that all have merit in the 6.5 Grendel. That's why I like it so much.

[rabiddawg]

Just give js8588 time. Before you know it he will be like many of us.

Multiple Grendels of varying length. You just can't help it.

[LRRPF52]

I've been thinking about cutting my original 16" AA Grendel barrel down to 14.5".

I shoot my 18" so much, the 16" has gotten neglected. I broke it all down because I never bedded that barrel anyway.

[BjornF16]

I had been running my 14.5" almost exclusively...now that I have a 11.5", I think both the 14.5 and 18" will collect dust.