Large Primer Pocket 6mms?

[MikeMcCasland]

Hey Guys,

Planning out a new build, and primer logistics is playing into it more than I'd hoped. I'm looking to build a 6mm that can burn Varget/H4350/N150 burn range powders, has quality brass, and can compete in F-Open out to 600, but do so with large rifle primer brass.

To my knowledge, that basically limits me to either the 6XC or the 6 Creedmoor. Are there any others that I'm missing?

I'm thinking of going 6CM because I don't see the XC winning out long-term against all the other 6mm contenders.

 

[6ShotsOr5?]

243 comes in LRP and I’m pretty sure you could do an AI version.

 

[6ShotsOr5?]

... And I know it’s not a 6mm, but a 25 Creed would be a good choice for 600 and Peterson sells 25 Creed LRP brass. Good luck.

 

[Bill K]

A 243 AI would probably work and it is not a lot to fire form cases. However the 6mm CM has factory brass/ammo and dies for sale, without having to get into form dies, etc. as would be the case with the 243AI.

 

[Ringostar]

You can also take lrp creed brass and size it down to 6x47L. Or consider a 6CM, use 243 brass and push the shoulder back to 30 degree. Oops, I just looked back at this. I meant to put 6slr, being pushed back on a 243 case. The 6CM is blown forward.

 

[mongo chicago]

David Tubb has had great results with the 6XC. I just had a Ruger #1 done in that cartridge for prairie dogs and can't wait till next summer to use it. Sighted it in at 500 yards on steel plates and accuracy was great. Using Norma brass, 37 grs. Varget, for 3192 fps. with the 87 gr. Hornady V-Max.

Forgot to say my 6XC is large primers.

 

[Ackman]

A 243 AI would probably work and it is not a lot to fire form cases. However the 6mm CM has factory brass/ammo and dies for sale, without having to get into form dies, etc. as would be the case with the 243AI.

No form dies required for the .243AI, or any AI case. Just load and shoot.

 

[R.Morehouse]

If you wanted a bit more neck you could take that brass (243) and do the 6SLR.

Regards
Rick

 

[10XSHOOTER]

A 6 creed with a 1-7 barrel and Sierra 110 SMK's can get you over 3100 fps.
works for me at 600 yds. I'm using Peterson LRP brass.
I also like the 6 SLR for longer neck. Make with .243 Win brass. (Not Lapua)

 

[MikeMcCasland]

A 6 creed with a 1-7 barrel and Sierra 110 SMK's can get you over 3100 fps.
works for me at 600 yds. I'm using Peterson LRP brass.
I also like the 6 SLR for longer neck. Make with .243 Win brass. (Not Lapua)

This is exactly the setup I'm considering. I like the 6CM because no forming, good LRP brass, and I've got a bunch of H4350, Hornady 110 A-Tips, and Berger 108 BTs.

Figure I could launch them about that fast (or faster) out of a 30" tube.

 

[swd]

The 6 Creed makes the most sense to me because of the great brass availability.

243 Ackley’s in particular are big time barrel burners in F Class. Sub 1K rounds.

A few friends and myself tried the bigger 6’s for F but ultimately we found the BRX and Dashers to have the advantage. The extra speed didn’t get us anymore points in fact we all shoot better scores with the smaller cartridges. But I get what your doing with trying to use components you already have.

 

[Laurie]

I'd agree that the 6mm Creedmoor looks the best bet in the circumstances with a bit less capacity than the XC but still suitable for H4350 and lots of decent brass around.

Anything larger capacity - ie 243 and its SLR or C-M offshoots - have capacity to bore area ratios that are best suited to slower burning powders. (That can be an advantage as they have the room to burn H1000 or Viht N165 and obtain a better barrel life than the XC because of their cooler burning characteristics - what I'm about to try out in the SLR.)

Why the LP primer requirement? Is that because of SR primer unavailability in the USA? (You did shoot the 6GT with great results in MR F-Open didn't you?)

 

[MikeMcCasland]

I'd agree that the 6mm Creedmoor looks the best bet in the circumstances with a bit less capacity than the XC but still suitable for H4350 and lots of decent brass around.

Anything larger capacity - ie 243 and its SLR or C-M offshoots - have capacity to bore area ratios that are best suited to slower burning powders. (That can be an advantage as they have the room to burn H1000 or Viht N165 and obtain a better barrel life than the XC because of their cooler burning characteristics - what I'm about to try out in the SLR.)

Why the LP primer requirement? Is that because of SR primer unavailability in the USA? (You did shoot the 6GT with great results in MR F-Open didn't you?)

I'm doing it because I have a bunch of Large Rifle Primers that I've collected over the years, but don't really have anything that shoots LR primers anymore (with exception to a 6.5CM, but I really want to shoot a 6mm).

I do have a 6GT (two of them actually), but those only use small primers. I shoot a lot of F-Class, but I'm only 'serious' about F-T/R, thus want to conserve all SR primers for that purpose; I've got enough to last through a year or two, but this mess could go on for a while, so I want to diversify.

All of my dabbling in 6mms is really just for use at a monthly 500 yard match. The other two matches I shoot monthly, I'll still be shooting F-T/R. I appreciate the kind words though, I wouldn't say I've done well with the 6s. I get my butt kicked every time I shoot open.

 

[Jdne5b]

Can you size a LRP Creedmoor case down to a 6GT?

 

[Laurie]

I get my butt kicked every time I shoot open.

Yup. I'm an ex-FTR now F-Open masochist myself. I reckon it's only because I can play with more rifles and cartridges than just 223 and 308.

 

[10XSHOOTER]

This is exactly the setup I'm considering. I like the 6CM because no forming, good LRP brass, and I've got a bunch of H4350, Hornady 110 A-Tips, and Berger 108 BTs.

Figure I could launch them about that fast (or faster) out of a 30" tube.

yes, you can get over 3100 with RL-16

 

[10XSHOOTER]

I'm doing it because I have a bunch of Large Rifle Primers that I've collected over the years, but don't really have anything that shoots LR primers anymore (with exception to a 6.5CM, but I really want to shoot a 6mm).

I do have a 6GT (two of them actually), but those only use small primers. I shoot a lot of F-Class, but I'm only 'serious' about F-T/R, thus want to conserve all SR primers for that purpose; I've got enough to last through a year or two, but this mess could go on for a while, so I want to diversify.

All of my dabbling in 6mms is really just for use at a monthly 500 yard match. The other two matches I shoot monthly, I'll still be shooting F-T/R. I appreciate the kind words though, I wouldn't say I've done well with the 6s. I get my butt kicked every time I shoot open.

Mike, I'm going to Barrel up a 6 GT this weekend for myself. What bullet and powder are you using?
I want to use 107 MK's moly with Varget. want to break that 3000 fps over my Dasher.

 

[10XSHOOTER]

Jdne5b, anythng under 40.0 grs of whatever powder can be lit off with a small primer. When you get over 40.0 grs. you need the large primer to get a good burn, especially if its cold.

 

[MikeMcCasland]

Mike, I'm going to Barrel up a 6 GT this weekend for myself. What bullet and powder are you using?
I want to use 107 MK's moly with Varget. want to break that 3000 fps over my Dasher.

I've shot 105 Hybrids, 107 SMKs, 108 ELDMs, 108 Berger BTs, and 110 Hornady A-Tips out of my two guns. Both of mine prefer H4350 over all else (I've tried N140, N150, RL16, H4350, Varget, and Shooters World Precision).

I hear N550 works really well too.

Personally, I think the cartridge is better suited for slower/H4350 type powders than it is for Varget (how it's marketed). Both my guns will give me 100+ FPS with slower powders, and consistently lower SDs.

Couldn't help you with a molly'ed 107 though. I can tell you 37.8gr of H4350 was pushing 'standard' 107s out of my 30" bart at 3030 FPS. It wasn't struggling to get their either; it was just most accurate there.

I'd recommend Hornady brass over Alpha in the GT. Just turn your necks and clean up the flash holes (they're not consistent in the Hdy brass).

 

[10XSHOOTER]

I've shot 105 Hybrids, 107 SMKs, 108 ELDMs, 108 Berger BTs, and 110 Hornady A-Tips out of my two guns. Both of mine prefer H4350 over all else (I've tried N140, N150, RL16, H4350, Varget, and Shooters World Precision).

I hear N550 works really well too.

Personally, I think the cartridge is better suited for slower/H4350 type powders than it is for Varget (how it's marketed). Both my guns will give me 100+ FPS with slower powders, and consistently lower SDs.

Couldn't help you with a molly'ed 107 though. I can tell you 37.8gr of H4350 was pushing 'standard' 107s out of my 30" bart at 3030 FPS. It wasn't struggling to get their either; it was just most accurate there.

I'd recommend Hornady brass over Alpha in the GT. Just turn your necks and clean up the flash holes (they're not consistent in the Hdy brass).

Mike, Thank you.