6mm & Slow Powders

[dtrostel]

HAVE any of you tried the super slow powders in the 244 Remington (6mm Rem, 6-257 Roberts, 6-7x57 Mauser)?

The research I have done on this site is mostly the 6mm with lighter bullets going super fast with fast burning powders.

I want more info on 6mm Rem but any input on other AI 6mm calibers will be appreciated (esp barrrel life - velocities - feeding from an AW mag)


Seems the latest craze is using larger capacity cases with slow burning powder to dramatically increase the barrel life. Sounds legit to me.

Example: 6 Competition Match, 6 Crudsader, 6AI, 243 AI, etc.. with either 50 gr H1000 or Retumbo. This should not only give decent volicities, it should have excellent case life (15 +/- doing neck sizing - anneal every 5 reloads with a full length size) and excellent barrel life. Reported velocities of 3200-3300 is not uncommon from my research, so my SWAG is a 6mm Rem with a shorter barrel should get at least 2900-3000 fps (my goal)

I have 3 friends shooting the 6 Comp MAtch (practically a 243 AI), and one has reported 4000 rounds before rebarreling with the slow powders.

Now im on the fence for a competition rifle in either 6xc, 243, or 6 rem (dont want to do fire forming) All the matches I shoot have a 3150 velocity limit so hot rodding it is not an option. My goal is to shoot the 115 dtacs from 2900-3000 from a 22" barrel( i realize this limits the velocity cause of slow burning powders, but shorter barrel is more important than a fast bullet). I will be using an AW mag, and for those not familiar, they give me an OAL of 2.98, so I will be able to load pretty long. Also, I will be using a short action with AW cut to utilize these mags.

the good thing about the slow powders is the low heat/pressure. I am pretty sure I wont be able to cram enough H1000 into a case to reach pressure, but if anyone can do a quickload I would appreciate it. from what research I have done, and it has been extensive, I am anitcipating 47-50 grains of powder to be used in the 6mm Rem case.

I like the 6mm rem case because it is steeper shouldered than the 243, and also a longer neck. Should help in the barrel life department.

SO, if anyone has any thoughts, concerns, experience, etc with 6mm and slow powder, short barrels and slow powder, I would greatly appreciate some input.

I have a 22" 338LM that I love (92 gr H1000 pushes 300SMK @ 2720) with good results. Hoping the slow powder/short barrel works out for a smaller cal.

The majority of my research of the 6mm Rem people have been using light weight bullets, long barrels, at super high velocities with fast burning powder. That is not my goal. My goal is 2900+ fps and a barrel life of 2500+ rnds.

Thanks again,
DT

 

[Steve Blair]

I shot a 6mm Remington in F-Class Mid Range loading IMR 7828 SSC. From 32", the load pushed 105 Hybrids at 3400 fps. They all made it to the target. The barrel overheated at around 10 rounds and dispersion increased dramatically. Bench testing produced groups around .25-.3" at 100 yards with ES under 15. Testing after the first match, shooting at typical match cadence, produced up to 150 fps velocity excursions after 14 rounds. One round was ~3550. Oddly, it did not blow out the primer pocket or show any other indication of over pressure. Regardless, I am satisfied that it is just too much powder to shoot 25 rounds. [br]
I've had four .244 and 6mm Rem rifles and "good barrel life" is not a phrase I would associate with them.

 

[357Mag]

D-Tros -

Howdy !

I've shot RL-22 and IMR 7828 in my 6mm wildcat, w/ case capacity between that of 6 X 47L and 6xC.
The chamber is made by running a 6mm Remington reamer in " short ".
My 6mm wildcat uses 7X64 Brenneke as parent brass,


In this case capacity and using 6mm bullets of 88-105gr... these powders were s-l-o-w.
I can fill the case w/ 7828 or 7828SSC; and pressures will be fine shooting even 95 & 105gr bullets.

43.7 IMR7828 and 42.0 RL-22 in my wildcat are ultra-high density loads. The RL-44 load nealry fills
the case completely.

Despite the 29" barrel, 43.7gr I7828 and Fed LR Match under Sierra or Berger 95's gives around
2,950 fps. Slow loads yes, but more to my liking & needs.... these loads are accruate.

I'm wondering whether a powder just a tad faster than RETUMBO would " fill the bill " for you ?


Best of luck in your endeavors !


With regards,
357Mag

 

[Valar]

I have same mindset , currently building a rem 8 twist shilen barreled 243. Waiting on the dtacs. I did score some reloader 25 and Lapua brass! Hopefully I will finish the gun in a couple more monthes. I work construction and am back to work. Work cuts my maching time way down. I started with a Shilen Barrel Blank 26 inches. I am curiuous to see if I obtain volocity. After further research using a 700 action with david tubbs over all COAL would need to go to a Long action! Im not going to do that so will most likley have no choice but to go a bit hotter with the a hotter powder! Tubbs Coal will not even chamber in a Short action. I will just have to expearment on my own.

 

[dtrostel]

I've had four .244 and 6mm Rem rifles and "good barrel life" is not a phrase I would associate with them.

kinda worried about that...

... most likley have no choice but to go a bit hotter with the a hotter powder! Tubbs Coal will not even chamber in a Short action. I will just have to expearment on my own.

Look into the AW Cut if you want a repeater. OAL of over 2.95 is darn long. But I also afraid will have to go with a hotter powder.

D-Tros -

Howdy !

I've shot RL-22 and IMR 7828 in my 6mm wildcat, w/ case capacity between that of 6 X 47L and 6xC.
The chamber is made by running a 6mm Remington reamer in " short ".
My 6mm wildcat uses 7X64 Brenneke as parent brass,

Despite the 29" barrel, 43.7gr I7828 and Fed LR Match under Sierra or Berger 95's gives around
2,950 fps. Slow loads yes, but more to my liking & needs.... these loads are accruate.

I'm wondering whether a powder just a tad faster than RETUMBO would " fill the bill " for you ?


Best of luck in your endeavors !


With regards,
357Mag

Thanks for the reply sir.

That is a very interesting wildcat for sure. only reason I ruled out x47 lapua and 6xc is price of brass. Also want little to no prep work for brass. My BR days of turning/weighing/sorting/ADD OCD are over for the time being. I want more time shooting less time reloading. My current rifle, 260, I sized brass down from 7-08 Win brass. The added steps bout wore me out. What does it take to make your wildcat out of 7x64 brass??


Which brings me to the 6 Super LR (for those not familiar http://www.6mmar.com/Super_LR.html
)

Looks tempting for sure. Slightly larger than the 6XC with the long neck and shoulder very similiar. Similiar capacity to the 243. hmmm

DARN OPTIONS!!

Regrads,
DT

 

[tonysnoo]

Which brings me to the 6 Super LR (for those not familiar http://www.6mmar.com/Super_LR.html
)

Looks tempting for sure. Slightly larger than the 6XC with the long neck and shoulder very similiar. Similiar capacity to the 243. hmmm

DARN OPTIONS!!

Regrads,
DT

It's definely been fun for me. I chose the 6SLR because I am such a novice. It's been a great caliber for me. The H1000 loads I tried were Ok, but my accuracy seemed to be best with 4831sc. So far it hasn't shot even my worst groups much over a minute and my best(400yd) was 1/4 minute.

The brass prep and loading are so easy, no fire forming. I think it's a real forgiving setup. I'm not running a fancy rig.....but it works great for me.

Good luck!

 

[357Mag]

D Tros -

Please check your PM's


With regards,
357Mag

 

[Hoser]

You know my thoughts on the 6CM.

I am a very happy camper.

Would not change a thing.

115s and H-1000.

 

[Tanner.]

I used to shoot Retumbo in a straight 243 Win with 105 Amaxes. I now shoot 7828 in a 243 Ackley with the same bullet. Great accuracy and pretty dang good velocity.

 

[LCazador]

Sleepygator has it right , the 6mm Rem , either improved or not , is a barrel burner and I would find it hard to believe any barrel shot at the cadence of a match regularly would last more than 2K rounds . I have shot the 6mm , the 6mmAI , and the big stomper 6X284 , and you're lucky to see more than 1500 rounds downrange before the bore goes south . The slowest powder that I've had good success with in all these cartridges is 4831SC and RE22 . Fast forward to the 6mm I'm shooting now , the 6X47 Lapua with 40 degree shoulder , Creedmore velocity with a lot less throat burn . I'm shooting 3400fps , with 108g Eubers . Great brass life , and my last bore scope inspection at 500+ rounds revealed a " like new " throat with no evident erosion . Now we're talking 3K rounds !! My personal theory is the steep shoulder along with the long neck keeps the turbulent point in the case and not in the throat . More to come on that theory applied to my new 221 Fireball , just finished !!