Grendel variant data

[TonyTheTiger]

I've been contemplating building an upper in either .22 or .243 Grendel in one form or another. Just wasted a chunk of my life bouncing all over the Internet including the Scout site and velocities are all over the board and spread across too many different threads to make any decent comparisons. So if you have a variant please post some data here, obviously including barrel lengths (manufacturer for bonus points) bullets used, powder, primers, velocity etc. Thanks!

 

[steve123]

Had a 6mm Rat, not the Fat Rat that is the improved version which I shoot now. Got 2640 fps with 105 hybrids in a 8 twist 20".

Shot a 22-6.8 for a few weeks, it was on loan for eval. 90 SMK at 2800 fps in a 24" 7 twist. I imagine you could get close to that with 90's in the 22 Grendel at the same length.

 

[TonyTheTiger]

Thanks for the info. I might have this moved to the semi auto section, I know there's more people around here running Grendel bastards....

 

[JBomb]

www.snipershide.com/shooting/forum/sniper’s-hide®-armory-supply/sniper-s-hide-semi-auto-rifles/6273840-224-predator

 

[TonyTheTiger]

www.snipershide.com/shooting/forum/sniper’s-hide®-armory-supply/sniper-s-hide-semi-auto-rifles/6273840-224-predator

I'm aware of that thread. It has some decent info but it's not the comprehensive collection of 22/6mm Grendel data that I would like to see.

 

[Yondering]

Tag for interest. I'm in the process of building a 243 Grendel variant as well; still haven't decided on a barrel, whether to order (from who?) or turn my own from a blank and a 6 PPC chamber reamer. Lead times on some of these barrels are almost as bad as buying NFA stuff! If any of you guys have a source for fast twist 6mm/243 barrels or blanks in stock, or want to sell a used one, let me know please.

I got interested in these variants after seeing ballistic tables for the 95gr and 105gr Bergers. Some guys are reporting 2950-3000 fps with the 95gr VLD from 22-24" barrels, and 2750-2800 with 105gr. That 95 VLD @ 3,000 might be the flattest shooting AR15 variant without going to a .473" or larger bolt face.

 

[TonyTheTiger]

I've seen those claims, but it seems most of them are made by people selling barrels. In the tidbits of info posted by end users that's scattered all over the web those claims look a little optimistic. Hence my thread hoping to gather some data in one place for comparison.

 

[steve123]

I've seen those claims, but it seems most of them are made by people selling barrels. In the tidbits of info posted by end users that's scattered all over the web those claims look a little optimistic. Hence my thread hoping to gather some data in one place for comparison.

When I was learning about the 6mmART40 cartridge there were some notable aspects of velocity, powers and bullet weights.

26" 8 twist Krieger barrel

I could get over just 2900 fps with AA2520/105 amax in the summer. I chose this powder because i had it on hand and it meters well. Brass was holding up decent with slight ejector smear. I abandoned that powder afterwards because by mid winter the same load had dropped 125fps. Lesson learned about temp sensitive powders.

Next load was 2875 fps with H4895. This was very accurate but only lasted till I got into another 8lb jug of H4895 which gave much higher pressures. Had to back off a grain and lost FPS.

Tried 115gr DTACS. Ladder gave 2675 fps for accuracy but decided against using them because supply was hard to get and barrel not twisted quite enough.

Barrel getting more worn and wanting to preserve it I worked up a light load at 2740 fps. This helped reliability but there was more wind drift than the other loads. I think the pressure of the previous loads grabbed the chamber wall too much so a hitch once in while with the hotter loads???

I've got some 95gr TMK's coming so I'll be trying them in the 6mmFatRat.

Next barrel might be a 22 Grendel with 90's.

 

[TonyTheTiger]

Thanks for the info Steve.