.308 or 6.5 creedmore AR build and barrel length.... Which should I choose and Y?

[K_Labs]

I already have a 18" .308 gap-10 but I am having another AR built . Its going to be either a 14.5" or a 24" the 30cal barrel is a bartlien blank and 1:10 twist.

Good idea? bad idea? Thoughts? Should I got 6.5? Would a 24" barrel be pointless because I alread already have a gap in .308? The reason I was thinking 14.5 is because I bought a 15" JP handguard and that would be awesome with a Babc pinned and welded on there.

 

[elfster1234]

I take it you reload? If so, either would be a good choice... If you already have a gap in .308 why not the 6.5 / 6creed if you reload that is.. It would be hard to justify a 14.5" in a 6.5creed.... 20" barrel is my call..... 6creed in a 20" would be some sexy shit.

Only thing that drags me back to .308 is the availabilty and price of reloading components. Im still going strong with my .308 even in hard to get components times like today.

I already have a 18" .308 gap-10 but I am having another AR built . Its going to be either a 14.5" or a 24" the 30cal barrel is a bartlien blank and 1:10 twist.

Good idea? bad idea? Thoughts? Should I got 6.5? Would a 24" barrel be pointless because I alread already have a gap in .308? The reason I was thinking 14.5 is because I bought a 15" JP handguard and that would be awesome with a Babc pinned and welded on there.

 

[K_Labs]

Yea I do reload and I have quite a bit of brass in .308 already. The only downside I see in 6.5 is that I don't have the dies or components

 

[bronco_buster]

Reloading component availability drives me toward 6.5 CM. Local sources stocked to the gills with 6.5 bullets and H4350. Try finding match components in 308--hit or miss--FGMM available if you want to spend $43 box! Haven't shot my 223 for 8 months due to availability and gouging for anything 223/AR related. I formed 100 Lapua 22-250 brass into 6.5CM. It was to prove i could get "Lapua" 6.5 CM brass. Ive lost count of the number of reloads on my Hornady 65cm brass after 10 firings. Out of an original 100, ive still got 75 going strong...gotta be in the neighborhood of 15 reloads by now. I anneal, shoot lower velocity spectrum, and begin using Wolf primers as the pockets loosen up. That said...it is my DTA SRS that gives the longevity. My 6.5 CM AR gets 4 reloads reliably, haven't gotten more than 6 without primers falling out of their pockets. But it's still so much more fun to shoot than the 308...you really deserve both.

 

[K_Labs]

So if I shoot 6.5 I don't need match components for match results? I also have a 6.5 grendel and I push 123's out of it so I have a few boxes of 123 laying around if that's not too light

 

[Fried Chicken Blowout]

So if I shoot 6.5 I don't need match components for match results? I also have a 6.5 grendel and I push 123's out of it so I have a few boxes of 123 laying around if that's not too light

If those are the AMax you have, I would not think they are too light... But they will not get you the same performance as the 140gr 6.5 bullets. It's my understanding that the 123gr AMax was specifically designed for mag length loading in the Grendel case so it was a compromise vs an optimized setup. Once you get into the 6.5mm bullets there's some amazing stuff out there. If you compare the Berger Hybrid 140gr BC 0.618 to the AMax 123gr BC of 0.510 or even the 140gr AMax BC of 0.585 you can see there's some advantages to looking around at other bullets. Those other bullets will also give you move flexibility with seating depth as well.

 

[K_Labs]

I have both amax and smk. So as far as barrel length goes what do u guys recommend? Is 24 too long? Also recommended twist rate?

 

[pkt1199]

I also have a 6.5 on order with GAP. I was torn on the barrel length as well - the best advice I got was to get it long and cut it down if you want it shorter in the future. You can always shorten, but lengthening, yeah...

That said I ordered a 22 inch. Just couldn't picture lugging around and maneuvering a 24" semi. Again - I've never had my hands on a GAP 10 with 22 or 24 so this is all just my opinion!

 

[Kiba]

14.5" or 24" is a big difference... you need to decide what you want to do with the rifle!

Regarding 6.5 or 308, again, you need to decide what you want to do with the rifle. I went 6.5 because in the last few years I've started shooting longer ranges and the 6.5 pulls way ahead of the 308 in that department.

I've got a 24" barrel with titan brake on my GAP10 in 6.5CM. I don't find it unmanageable but I was prepared to send it back to have it cut down if I didn't like it. I'm glad I went with the 24" barrel now as the rifle needed all the help it can get in the velocity department; factory Hornady 140gr ammo runs 2780fps out of it but pierces about 30% of the primers. With my handloads 2740 is about as fast as I can safely push it with 140/H4350/210M and keep the primers intact. Next step is to try Wolf LR or CCI 34 primers (both of which are supposed to have a thicker cup than the 210M) to see if that improves primer condition. With 2" less barrel I wouldn't be surprised if I could only get 2690fps out of it while keeping the primers intact.

My JP LRP-07 in 6.5CM is coming with a 22" barrel because that's what JP offers-- should be interesting to see how it does compared to the GAP10 in terms of primer condition and velocity with similar loads.

 

[soteaser]

I have a savage long range hunter and with the 24" factory barrel it shoots exceptionaly well. (6.5 cm that is) have a few. 308 v.g. shooters too, and i am glad the choice was the creedmoor. Very fun to shoot and so far no issues with primers, but i don't push it either, no need to. Been using amax 120's, 95's, and beger 140, 130, 120, also tried a few nosler cc 140's all with good results using loads from manuals. The vld's took me a while to find sweet spot (2.835"-about .020-.030 off lands) but now they are great. The only bullet that gives me trouble is the horn 123 vmax, and i wonder if it has something to do with the apparent grendel design?
Also, i'm considering a barrel for ar, and a bit shorter would be nice, please post what your final choice of length and results are, very interestd. Whatever you go with good luck and good shooting!
Lessdrop
P.s. any ideas why the 123 vmax are finicky for me? Thanks.