25 Grendel Gas Gun???

[DoNotReply]

Been tossing around the idea of a 25Grendel in the AR-15 platform. I’m still a beginner/novice in the shooting world.
So, has anyone tried a build centering around the BJ 131 ACE? Or do you think it would have the same issues as other Grendel cartridges?
Remember all I know is what lil I have read so forgive my ignorance in advance.

 

[TonyTheTiger]

Without actually taking any measurements I would guess that the 131gr Ace is too long of a bullet to really be a good fit in the Grendel, probably displacing too much powder capacity to get acceptable speeds. I'm happy to be proven wrong though.

 

[DoNotReply]

@TonyTheTiger
Yea I was thinking that as well. But have a feeling that a 25 Grendel would make a really good AR platform. Possibly something in 110gr-120gr would be a good fit.

 

[Snuby642]

What would you gain over the 6 and 6.5 offerings?
I know nothing about 25. So actually a question.

 

[DoNotReply]

What would you gain over the 6 and 6.5 offerings?
I know nothing about 25. So actually a question.

Once again from what I have read on here and a few other sites.
A BC of a 6.5 with a 6 low recoil.
Sporting splashes down range while keeping a flatter trajectory.
Pretty much a lot of the goods from the 6.5/6 mixed into one bullet.

 

[TonyTheTiger]

Most of that is really only applicable to short action cartridges. With the Grendel being a much smaller cartridge you already have low recoil, good barrel life, potentially very hard to spot misses. If I was going to wildcat a Grendel I'd just go all the way down to 22 cal as it seems most fitting for the case size unless you want to go hunting.

 

[Snuby642]

I imagine high velocity ensues?

My 6.5 g is slow in comparison , but accurate and not much on recoil.
I got it intent to have longer barrel life but had to give up speed.

Makes for a good old guy gun cant wait to start loading for it.

So far factory rounds are just under 1moa 123 sst with my can adapter on.
Went to hell with the can 2.5+ moa.
If my handloads don't correct that the birdcage goes back on, it shot better with that.

Will wait for those tests since I rockset the adapter in place, may even get a thread protector instead?

 

[steve123]

Years ago I was able to get the 115 DTACS going 2650 fps in my 26" 6mmAR-T40, and this was mag fed, but the long bullet was taking place of some powder. I've long since settled for 95 grainers which have been the best compromise of speed and BC.

With the 22 caliber version I'd be worried about the long bullets, "88-90 grain" blowing up in 6.5-7 twist after the throat starts to fire crack. This has happened to me with other calibers and I don't want to take the chance again. 80's seem to be a sweet spot though, sacrifice some BC but gain some speed, kinda like the 95's I use in the 6mm FatRat.

Except for single loading in a AR I wouldn't want to attempt the 131Ace in a Grendel, or use the lowish BC lighter weight 25's.

I think I've learned my lessen of staying with "normal" to avoid possible hassles. I aim out a tad more for wind and enjoy reliability.

 

[Mike_in_FL]

I would only do this in a large frame .25 Creedmoor with specific twist for the 131s.

 

[Big Moose]

Years ago I was able to get the 115 DTACS going 2650 fps in my 26" 6mmAR-T40, and this was mag fed, but the long bullet was taking place of some powder. I've long since settled for 95 grainers which have been the best compromise of speed and BC.

With the 22 caliber version I'd be worried about the long bullets, "88-90 grain" blowing up in 6.5-7 twist after the throat starts to fire crack. This has happened to me with other calibers and I don't want to take the chance again. 80's seem to be a sweet spot though, sacrifice some BC but gain some speed, kinda like the 95's I use in the 6mm FatRat.

Except for single loading in a AR I wouldn't want to attempt the 131Ace in a Grendel, or use the lowish BC lighter weight 25's.

I think I've learned my lessen of staying with "normal" to avoid possible hassles. I aim out a tad more for wind and enjoy reliability.

Just curious, did Whitley make you upper?

 

[steve123]

Just curious, did Whitley make you upper?

Yes he did. I sold it later then regretted that decision shortly after.

I had a 6mm FatRat done this time.

 

[Big Moose]

Yes he did. I sold it later then regretted that decision shortly after.

I had a 6mm FatRat done this time.

I know it's essentially the same as the Turbo 40, but how does your RAT build compare to Whitley's?

 

[steve123]

I know it's essentially the same as the Turbo 40, but how does your RAT build compare to Whitley's?

The Wilson 6mmFatRat barrel isn't quite as accurate as the Krieger in the 6mmART40 was "at first". Next time around I'll get a Bartlein or Krieger in 6mmFatRat. Except for not shooting 105 hybrids well I'm content with this barrel, it shoots sub moa with 95gr SMK. This upper definitely runs better than the 6mmART 40 ever did.

The barrel extension/barrel came loose in the Whitley upper over time, gradually becoming worse, it took me 500 rounds/6 months to figure out why I was having POI shifts. I tried a new scope, rings, etc and at the end of the headache I actually cracked the extension loose with my bare hands, that pissed me off. Supposedly this happened from some warm loads I used, don't know if I believe it though I suppose it's possible, some excuse huh, ?? Ehh, I won't be using him anymore because I thought he should have offered a deal on the next barrel or some kind of compensation, I didn't even get an apology.

 

[FCS]

@TonyTheTiger
Yea I was thinking that as well. But have a feeling that a 25 Grendel would make a really good AR platform. Possibly something in 110gr-120gr would be a good fit.

115 Berger VLD on heavy side for higher BC, OTM bullet.
100 Nosler or 115 Nosler BT would probably be best all around bullets, much like 100 & 120 in 6.5 Grendel.

Honestly, don’t see 25 Grendel gaining you anything in a gas gun over 6.5 Grendel.

131 ACE in a 25 Grendel will need a much longer OAL and would do decent in a bolt gun. I have a custom built 6.5 Grendel bolt gun set up with a chamber optimized for 130 JLKs, OAL of 2.600” ish and while fun, very accurate is not very zippy. IIRC, 130 JLKs @ 2600 from a 26” bbl.
25 Grendel will be same same, if anything slightly worse due to case capacity / burn rate of powders / bore size slightly smaller.

 

[Peterpan]

The Wilson 6mmFatRat barrel isn't quite as accurate as the Krieger in the 6mmART40 was "at first". Next time around I'll get a Bartlein or Krieger in 6mmFatRat. Except for not shooting 105 hybrids well I'm content with this barrel, it shoots sub moa with 95gr SMK. This upper definitely runs better than the 6mmART 40 ever did.

The barrel extension/barrel came loose in the Whitley upper over time, gradually becoming worse, it took me 500 rounds/6 months to figure out why I was having POI shifts. I tried a new scope, rings, etc and at the end of the headache I actually cracked the extension loose with my bare hands, that pissed me off. Supposedly this happened from some warm loads I used, don't know if I believe it though I suppose it's possible, some excuse huh, ?? Ehh, I won't be using him anymore because I thought he should have offered a deal on the next barrel or some kind of compensation, I didn't even get an apology.

I had Lee wells assemble me a fat rat with a 26” Krieger. He does good work. I’ve since sold it and had a smith put together a 6br on the ar15 platform for me.

 

[Peterpan]

Been tossing around the idea of a 25Grendel in the AR-15 platform. I’m still a beginner/novice in the shooting world.
So, has anyone tried a build centering around the BJ 131 ACE? Or do you think it would have the same issues as other Grendel cartridges?
Remember all I know is what lil I have read so forgive my ignorance in advance.

I would love to see a 257 cal Grendel variant. But I’d probably start with an improved version like the turbo 40 improved or the fat rat case and neck it up to .257 from .243. The shoulder angle is an improvement and it may save you some powder capacity with that long high bc black jack bullet