~28xx fps with a 6mm creedmoor, yeah or neh?

[SuperBruce]

I want to add a 6mm to my collection but want to sidestep the 'one season, maybe' barrel life of 6mm creedmoor. The option I'm considering is to light load 6mm creedmoor hoping to get more life from it, my goal being 2500+ rounds. That would also give me to option to crank up the speed if I want/need to. However, I've yet to see anything more than suggestions as to whether this even works to extend barrel life or that it's not like having teeth pulled to find a good load at that velocity with 105+ grain projectiles.

I know the most obvious solutions are 6 dasher or 6mm GT but I'm not super excited about getting into the wildcat game: it's nice to be able to buy a box of ammo, dies, brass, or whatever, from the local sporting goods store and I'd prefer not to roll the dice on magazine issues. There is the 6mm arc but it's a little on the anemic side and I have similar magazine concerns as with the dasher.

Thanks in advance!

 

[longgunJR]

Why not just run a 6.5? you'll get 3k or so barrel life and with a good brake like an APA gen3 Fat Bastard you're really not giving up much in terms of more/less recoil. Yes it'll kick a bit more but it's more than manageable.

 

[Dogtown]

Sounds like a good experiment to embark on for the Hide. You could use a slightly slower powder like H4350 so that you still maintain safe case fill % and keep the pressures down while still getting 2800-ish fps. Just keep a meticulous log of round count and monitor barrel wear. Maybe someone else will try something similar so we don't have a sample size of one? I say go for it!

Thank you for your service...

 

[SuperBruce]

Why not just run a 6.5? you'll get 3k or so barrel life and with a good brake like an APA gen3 Fat Bastard you're really not giving up much in terms of more/less recoil. Yes it'll kick a bit more but it's more than manageable.

Because I already have one of those + a hellfire brake and it's certainly great but I like to try new things.

You're certainly not wrong, if I was smarter about this I'd instead invest in a 223 training barrel and just shoot shoot shoot. And who knows, maybe I will after a few more of you talk me off this cliff.

 

[Dogtown]

Jump! Jump!

 

[just browsing]

It’s feasible for sure.

We tested 2 identical 6 Creed Brux barrels, from the same batch, cut with the same reamer one after the other, same length and contour. Both were threaded for EC tuners and were shot with Mavericks on the end. One barrel was fed nothing but Berger factory loaded 105s and the other barrel got nothing but FGMM 105s. We shot the same matches, same training days, same everything with them.

The Berger ran just under 3,000 fps (I think it was around 2,985) and the FGMM ran up around 3,160fps.

The FGMM barrel was torched in about 1,200 rounds, started bleeding velocity and groups opened up considerably. We got the Berger barrel to about 1,500 rounds before we lost interest and went to BRs. That barrel is still shooting fine and we’re planning to go back and finish it off at some point, but the bottom line is that velocity & pressure (and by extension, heat) have a clear and obvious impact on a barrel’s longevity.

Certainly wouldn’t say “keep it under 3k and you’ll get 1500 rounds easy,” but you’re much closer to the realm than running Creed flat out would be.

 

[JBoomhauer]

I’m going to say go with a more efficient design.

Why burn all the extra powder for BR type numbers? You get less barrel life, more heat into the barrel on the longer strings of fire. More mirage off barrel\can.

You can buy brass for the dasher, so as far as reloading it’s no different than a 6creed.

 

[Mr. Z]

Jump! Jump!

 

[Dogtown]

My kind of gallows humor...

 

[SuperBruce]

Sounds like a good experiment to embark on for the Hide. You could use a slightly slower powder like H4350 so that you still maintain safe case fill % and keep the pressures down while still getting 2800-ish fps. Just keep a meticulous log of round count and monitor barrel wear. Maybe someone else will try something similar so we don't have a sample size of one? I say go for it!

Thank you for your service...

Ha, fair enough! You're like the angel/daemon that stands on the opposite shoulder of @longgunJR. Hodgdon shows plenty of data for loads in the mid 40k psi but it's a matter of whether going to actually preserve barrel life to the extent I want and if a good load can be found that low. Most powder isn't intended to be burned at that pressure so I'm a bit pessimistic. I'm okay sacrificing a barrel for science, that's just a matter of $$$, but I'm much less interested in spending half a season trying to find an acceptable load.

You can buy brass for the dasher, so as far as reloading it’s no different than a 6creed.

As far as dasher I really just don't want to mess with magazines, that is the straw the broke the camels back. I hear it's not the problem that people say it is but I also don't want to find out the hard way for my specific setup. Maybe there is a thread about that somewhere... I have all magpul furniture right now, magazines, 700 pro chassis, and an origin action, and maybe it works fine but I don't know where to find out other than try it.

 

[Tokay444]

I get 2850-2860 out of a straight BR with 105s and Varget without batting an eye, and it's a BR.

 

[Changed]

Bryan Litz mentioned downloading a 338 Lapua to less than half case fill with varget, yet still getting excellent accuracy.

 

[Dogtown]

<70% case fill % is generally considered bad news, so I would assume he added some filler in order to prevent a detonation?

 

[acourvil]

I haven’t tried it, but I think you could run H1000 at 2800-2900 and get 2500 rounds or so. IIRC, David Tubbs was doing this eight 6XC a while back. I did run some rounds with H1000, and got to that speed range with good accuracy, but wanted a bit more speed.

 

[spife7980]

Shoot it where its most accurate. Do a wide ocw and check. I dont think the "saving a bit of barrel life" thing will ever really work when youre shoving 39 grains of powder down a hole smaller than a quarter inch.

Ive been having the inverse struggle trying to make my little shorter 140 gr 6.5 shoot faster but it is liking 38 gr of 4350 at 2480 fps over basically everything else. So Ill take the small groups and proceed with my calculator to match because thats what it does best.

 

[cgobeli]

I am currently running 37.7gr of H4350 in my 6 creed with everything from 105 Scenars, 110 A-tips, and 109 hybrids, and I am getting around 2840 (24" barrel). I will probably change the barrel out at the end of the season (should be around 2k rounds through it) just so I do not have to deal with it next season.

My factory barrel on my RPR had just over 2k through it, changed it to prevent issues, and the barrel currently on my RPR is just over 2k on it and still shoots fine and I haven't has an issue with velocity dropping.

So, I believe you can run them slower and probably gain additional barrel life, or maybe I don't notice when a barrel is toast.

 

[LV Precision]

@SuperBruce I've done the exact thing you're looking to do. My practice barrel runs a 6mm Creedmoor at 2860 running 38.5gr H4350 with Barnes 112, and Hornady brass. I've got 700 rounds down the pipe, easy sub-0.5 MOA. FYI, my match gun runs a 6 Dasher with Berger 109 with 30.5gr Varget at 2767.

There are a few reasons why I'm running a 6creed this way:

• Use cheap Hornady brass ($0.35/piece for virgin brass)
• Use large rifle primer (vs. small rifle primer for my Dasher)
• Use H4350 (vs. Varget for my Dasher)
• Easily available barrels in a 6mm

I anticipate running this to 2000+ rounds, and have heard others like Jake Millard doing the same thing. The case isn't as efficient as a BR-based caliber, but so far it's been working well, and it allows me to save the Varget and SRP for my match gun. I'm using Barnes because they're super cheap (vs. Berger) and still capable of hitting 1MOA plates at distance.

 

[awp762]

Sorry no data on a 6mm CM but i have run 5,194 rnds through my 6XC.

bbl #1 @ 2468,
bbl #2 @ 2,497,
bbl #3 @ 229
all Bartlein 7.5tw 5r
all 115 dtacs with a few 107 smk's used on bbl #1

bbl #1 still has some life left even though the throat is worn, about 1" jump to lands
mostly BN coated tips except the last 500 or so
haven't tested this one past 100 since pulled.

bbl #2 still has life left still measuring to lands in thousandths, all 115 dtac bare
still groups well @ 1k

bbl#3 just started on it. Decided to use it since bbl #2 is getting up there in round count & wanted to check loads on bbl#3
115 rbt dtacs

I don't chase the lands, just use the same seating depth as the original setting 2.080" base to ogive.
I only check it to see where the lands are at to see how much possible life is left.

bbl #1 used 37.0 H4350 @ 2732 fps & 38.5 H4831 s/c @ 2635 fps
Only used H 4831 s/c due to the last huge powder shortage a few years back
28" bbl length

bbl #2 used 37.4 H4350 @ 2798 fps
28" bbl length

bbl #3 used 37.4 H4350 @2889 fps
30" bbl length

bbl #2 will be re-installed to see when it shits the bed

Lastly i use 44.1gr H1000 @ 2898fps in my 243 due to the last powder shortage, grouped so well i haven't tried H4350
I have never cared about speed only accurate loads

 

[SuperBruce]

There we go, data!

@mtruong, sounds like your 6 creed is doing really well, why have the dasher on top of that? Just for that extra few percent performance, so you know you have a rifle in pristine condition for match time, or is it just a component availability divide-and-conquor strategy? Every primer and lb of H4350/Varget is precious these days...

@awp762, sounds like you're getting to where I want to be, albeit with a 6xc. Why the huge disparity between barrel 1 and 2 in terms of throat erosion? The way you used it, just luck of the draw, or do you think h4831sc had anything to do with it? It seems the common wisdom is slower powder -> longer barrel life but that runs counter to it.

 

[Force_Multiplier]

I want to add a 6mm to my collection but want to sidestep the 'one season, maybe' barrel life of 6mm creedmoor. The option I'm considering is to light load 6mm creedmoor hoping to get more life from it, my goal being 2500+ rounds. That would also give me to option to crank up the speed if I want/need to. However, I've yet to see anything more than suggestions as to whether this even works to extend barrel life or that it's not like having teeth pulled to find a good load at that velocity with 105+ grain projectiles.

I know the most obvious solutions are 6 dasher or 6mm GT but I'm not super excited about getting into the wildcat game: it's nice to be able to buy a box of ammo, dies, brass, or whatever, from the local sporting goods store and I'd prefer not to roll the dice on magazine issues. There is the 6mm arc but it's a little on the anemic side and I have similar magazine concerns as with the dasher.

Thanks in advance!

Look at my 6ARC thread

I got 2742 (on a brand new barrel) with Hornady black 105s

2780 with hand loads that group and are super consistent and easy… 2840-50 max book charge of CFE223, zero pressure signs yet

I ran a 243 for over a decade and tried 6CM… even down to 2860ish I never got over 2500rds on a barrel

 

[LV Precision]

There we go, data!

@mtruong, sounds like your 6 creed is doing really well, why have the dasher on top of that? Just for that extra few percent performance, so you know you have a rifle in pristine condition for match time, or is it just a component availability divide-and-conquor strategy? Every primer and lb of H4350/Varget is precious these days...

@awp762, sounds like you're getting to where I want to be, albeit with a 6xc. Why the huge disparity between barrel 1 and 2 in terms of throat erosion? The way you used it, just luck of the draw, or do you think h4831sc had anything to do with it? It seems the common wisdom is slower powder -> longer barrel life but that runs counter to it.

The Dasher is just a better match caliber; less recoil with a more efficient cartridge, better SD/ES, and inherently accurate.

But really, running a 6creed gives me a way to utilize components that I generally have on hand in sufficient supply (Hornady brass, LRP, and H4350) while still running a relatively mild load for a 6mm bullet.

 

[jakelly]

6mm Comp Match. Guys have gone over 5k rds using H1000 and 105-115s.

 

[awp762]

There we go, data!

@mtruong, sounds like your 6 creed is doing really well, why have the dasher on top of that? Just for that extra few percent performance, so you know you have a rifle in pristine condition for match time, or is it just a component availability divide-and-conquor strategy? Every primer and lb of H4350/Varget is precious these days...

@awp762, sounds like you're getting to where I want to be, albeit with a 6xc. Why the huge disparity between barrel 1 and 2 in terms of throat erosion? The way you used it, just luck of the draw, or do you think h4831sc had anything to do with it? It seems the common wisdom is slower powder -> longer barrel life but that runs counter to it.

I think the big reason why bbl # 1's throat wore out was due to excessive amount of the bn coating on the dtac bullets i used for it or maybe the bn coating itself.

There was enough coating to scratch my redding dies. After i noticed this on the dies & after i sent them to redding to get fixed, i started putting the bullets into a cardboard box & shaking them to remove "what i believe" was excessive coating & shot some more. I don't use the bn coated stuff anymore.

bbl#2 & bbl #3 has never used the bn coated dtacs & shoots very good with the bare dtacs.