Want a Grendel upper for some long range use, barrel length question mostly

[Lawless]

I am contemplating a Grendel upper for long range shooting, perhaps to 1000 rarely.

I am finding conflicting information regarding barrel length/velocity.

What is the real skinny on 18 vs. 20 inch velocity? Some say no real difference and some say as much as 100 FPS.

Also, is one mag brand really better than the others for this cartridge?

 

[strike33]

I have 2 18" barrels, my next will be a 20". Running the numbers the 20" certainly gets past 1,000 more reliably.
The Quality of the E-Lander mags is far above the C-Products, however neither has caused me issues.

 

[just browsing]

Either go really long (24”+) or really short (12”-).

 

[krw]

Go to 65Grendel.com. Buy the 2 books on Grendels. Worth the money if you have or want a Grendel. My next Grendel will be a bolt w 22”bbl

 

[bullseye13]

I love my 16". 2400-2450 with hornady SST's. MOA to 8-10" groups at 800yrds, but great for practical shooting to 300yrds.

 

[AZgeek]

Sounds like this is not going to be a dedicate bench gun so if you want to keep it light enough for other applications 18" will be the best compromise.

 

[Strykervet]

Either go really long (24”+) or really short (12”-).

This is exactly what Bill Alexander told me years ago when I was in the army and had a relationship with him testing the Beowulf for use as an alternative upper to keep in the Strykers. It fell through but a demo we put on for the war college sold it off to the Coast Guard for one. And I got to keep the test mule, a Beowulf upper with a KAC FF rifle length tube (which was also new then). Anyway, we'd talk on the phone from time to time and when I built my Grendel around a Satern bbl., he recommended 120gr. Nosler BT's (and he was right, I get .33MOA with those and only those).

But he also said before I got it that if I wanted it short, get it short, and if I wanted it long, get it long. The way it loses velocity per inch, this sort of makes sense, but a 20" is what I went with and it's sorta the best of both worlds.

Really you can't go wrong, but yeah, SBR'ing an 11.5" (like I have, a Lilja bbl.) makes it easier to get in and out, maneuver if you're gonna go short and the 20", well, 22" or 24" would have given more velocity but the 20" just does it for me.

Haven't shot the 11.5" but I have great expectations from it with 107SMK's or 100gr Hornady AMAX. Plan on loading for it again when I get my trim die and the Dillon conversion.

 

[Shadow knows]

Do you reload?

 

[Shadow knows]

I went with a 20” proof barrel and Maxim bolt and have had no issues. We have noticed a timing issue with the Grendel and shorter barrels when starting to push speed out of them. Once we settled on 20” barrels our problems started going away.
Grendel forum is pretty good info

 

[Shoots 700's]

What bolt did you use .125 or.135?

 

[Danattherock]

20". Specialized Dynamics in Arizona makes tack drivers. Got one last year for gas gun matches.

 

[newguy2k3v2]

Really you can't go wrong, but yeah, SBR'ing an 11.5" (like I have, a Lilja bbl.) makes it easier to get in and out, maneuver if you're gonna go short and the 20", well, 22" or 24" would have given more velocity but the 20" just does it for me.

Haven't shot the 11.5" but I have great expectations from it with 107SMK's or 100gr Hornady AMAX. Plan on loading for it again when I get my trim die and the Dillon conversion.

You'll like it. I have that barrel and that gun has turned into my do all hunting rifle(within reason). VERY accurate and compact for in and out of vehicles with NV and ir laser but can still hit steel at 750 if I want to.

 

[bldsmith]

I have several, 10.5,12, 16, 18, 20 and 24. I have been drawn heavily to the 12. 90% if what I do will be done with the 12. The 18 is a nice intermediate. 24 is for tack driving and longer range.

I started with the type 1 chamber from bhw 20". Second time out the extractor failed. Same thing with my 10.5. I have replaced 4 extractors so far. I began buying type 2 chambers(saami). I will probably sell or give the type 1 chambers away. Too bad the 20" is very accurate.

 

[az 762 nato]

I also have the 11.5 Lilja among a few other Grendels, it really is a great balance between length and velocity, smoked a yote a few weeks ago at a tick over 715yds

 

[Snuby642]

Barrel length / muzzle velocity, 25 fps per inch works close for an estimate.

 

[Lawless]

Thank you gentlemen

 

[Niles Coyote]

The difference between my 18 JP Enterprise barrel and my 20" Bartlein barrel is 15-20fps with 123 grain bullets. The difference between my 16" ballistic advantage and the 18" jp is around 60fps, all using the same load with 123 grain bullets. Keep in mind different bullet weights and powders may change that.

 

[Lawless]

The difference between my 18 JP Enterprise barrel and my 20" Bartlein barrel is 15-20fps with 123 grain bullets. The difference between my 16" ballistic advantage and the 18" jp is around 60fps, all using the same load with 123 grain bullets. Keep in mind different bullet weights and powders may change that.

So really, after 18” the returns are very slight?

Sounds like an 18” may be what I am looking for.

Rifle gas and an adjustable block preferred correct?

 

[bldsmith]

If you are going to shoot out to 1000 with any regularity, the 20" would be my choice. The speed difference between the 18 and 20 listed may also have something to do with the different mfg. I would expect a slightly larger difference though not dramatic. I will be paring down my 6.5 heard. I will probably keep a 12, 18 and 24". These seem to offer the best performance range without heavy duplication/overlap.

I have 2 18", one with mid gas and one with rifle. Both work fine with factory loads.