IMR 7828SCC with 6MM Creedmoor

[Starlite]

What he said. 7828 will work, but your velocity will suffer.

I'm certainly not disputing his input as it's real world testing. however, as I said to @jasonco, the Speer data for their 100gr SP as does the Hornady data that I just looked at (although for 105gr)...last two on list

 

[Starlite]

Try Staball powder instead if you can find it, it's amazing in the creedmoors.

Yeah I have 6 pounds. Reloading powder availability is insane so reluctant to use. Care less about the 7828 as I don't have a magnum anymore. I'll be trialing it with the 109gr hybrid tgt I have coming.

 

[Mike Matteson]

Make no mistake, that 6mm Creedmoor is in fact an overbore cartridge, in behavior and slow powder selection. Here's a 90TGK test.
View attachment 236630

Thanks for the add info on jkl devise.

 

[Starlite]

Thanks for the add info on jkl devise.

Can you elaborate..jki devise? Forgive my ignorance

 

[elimsprint]

I've been using 7828SSC in my .243 for years with 87gr Bergers and Hornady's and it works great. It had the best velocity and accuracy of all the powders I tried in my Savage. I got it from an old Berger reloading info email I got from Berger before they did their manuals.

 

[rbTanzan]

"My go to powder for 6mm Creed is RL23. H4831SC works well as does RL26. H1000 is usually a little slow with the 115 DTACs that I shoot in it. Best of luck!"

You can add the new IMR7977. It is close to RL25 and RL26.
IMR7977 is very dense so you can pack a grain or two more into a case than some powders. Hodgdon and Nosler list it for the 243Win with 100gn bullets. I also found that it worked better than H4831sc in a 270 when loading 180gn Woodleighs, producing about +100fps and good accuracy. Try a ladder and see if you get a promising node and velocity. Here is a pic of the 100-yd., 180gn ladder from 56gn to 58gn 7977, velocities 2539, 2569, 2573, 2634(2shot avg), 2653. (For comparison, H4831sc maxed at 55gn, 2597fps, [inaccurate 3-shot group 2"].)
Primers all good, pic follows.

Rifle likes 2635fps 57.5gn IMR7977. Tikka T3x, 270Win, 22.4" barrel.

 

[DJ Fergus]

I have some Berger 90gr tgt projectiles that I'm wanting to shoot out of my 6mm CM. I usually try to load powders that have a Load Density above 95%.
I found some data in my swift manual however it's for the 243 that show promise for 7828. (42.3-45.5gr with a 90 gr swift scirocco II)
It pays to buy powder when you find it. So..I have some IMR 7828 and 7828SCC. I think I can get ~ 43.5gr (max) am I way off with this amount.

anyone have experience with IMR7828 in their 6mmCM?

The 7828 may be better to try with 105 plus weight bullets. I know that wasn't the question you asked. You could still try the 90s with it. You may run out of case capacity as stated. Try a long drop tube funnel to get more powder into the case if you have issues with running out of powder space in the case.

 

[greenejc]

I have some Berger 90gr tgt projectiles that I'm wanting to shoot out of my 6mm CM. I usually try to load powders that have a Load Density above 95%.
I found some data in my swift manual however it's for the 243 that show promise for 7828. (42.3-45.5gr with a 90 gr swift scirocco II)
It pays to buy powder when you find it. So..I have some IMR 7828 and 7828SCC. I think I can get ~ 43.5gr (max) am I way off with this amount.

anyone have experience with IMR7828 in their 6mmCM?

Your velocities will be a little low, but because of its burn rate, it should work in your rifle at a 100% fill for your casing. The Hodgdon site doesn't list the 6mm Creedmoor with this powder because of its slow burn rate, but it does list the 6mm Remington with a max charge of 44 grains with the 95 grain Nosler Ballistic Tip. Their new 2021 book lists it for the 243 Winchester, however. Starting load is 45 grains, max load is 48 grains. This is with the Speer 90 grain bullet. You should be ok with 44 grains and still well within max SAAMI pressures, but start low and work up. Its a slow powder, more suitable to the 6mm Remington or above, due to case capacity, and won't give you really high velocities, but if it gives you good accuracy at say 2800fps ave., you're still minute of Prairie dog out to around 400 yards, so who cares? I like it in the 25-06 and the 6mm Remington with most of the bullet weights I shoot.

 

[fmuguira]

I m shooting 42 grs of IMR4831 with a 105 grain bullet and getting 3050 FPS. 23.5" barrel. There's room for more but it shoots 1/2 MOA out of the 8 twist Lilja so I m happy. Since I have a lot of IMR4831 and minimal 4350 I thought what the heck; try it. I think IMR7828, especially short cut, will work you just might not get full velocity but case will be 100-105% !

Use a drop tube and also consider stepping up to 105-110 gr bullets. Good luck!

 

[greenejc]

Yeah I have 6 pounds. Reloading powder availability is insane so reluctant to use. Care less about the 7828 as I don't have a magnum anymore. I'll be trialing it with the 109gr hybrid tgt I have coming.

Give it a try with the 90 grain bullet. Because of its burn rate, it may be slow(relatively), but it should post upwards of 2900fps with a max load(case capacity). You're almost guaranteed not to max out your pressure with this powder. I also use it in my 300 WinMags for 200 grain bullets. All I can say is give it a try.

 

[Huntz]

I have found H4350,RL 16 and 6.5 Staball to give me my best groups in 2 6MM CM using 112 grain Barnes bullets,Win.LR Match primers and Starline brass.I was shooting for best accuracy and not highest velocity.

 

[Hugnot]

The 6.5 CM has roughly similar case capacities as the .243 W, depending on bullet shape & seating depth.

Hodgdon data has .243 W data for 48.0 gr of 7828 with a 90 grain bullet at 50.6 CUP with reasonable velocities of 3130, about 5 % lower than max velocities shown. The short cut 7828 might allow an increased charge.

Not optimum but useable.

I use Rem 7 1/2 primers in my 6.5X47 L with H4350 & such with no problems.

 

[fmuguira]

Before I built CM I shot 48 grains of Retumbo in a 26" Rem 700 VLS with 105 AMax and it shot sub-moa at 3050 FPS with a 9 1/8 twist factory barrel and 2.810" oal. The 6 CM is close to the 243 on case capacity due to design so I ll be shocked if you can't get some workable loads with 7828. As I mentioned earlier my current 6 CM does fine with IMR4831.

BTW, that Retumbo load in 243 was a full, full case... could hear powder crunch slightly when seating bullet. And, I had to bounce case and trickle powder in to make it fit! lol. Probably should of used a drop tube

 

[Starlite]

The 7828 may be better to try with 105 plus weight bullets. I know that wasn't the question you asked. You could still try the 90s with it. You may run out of case capacity as stated. Try a long drop tube funnel to get more powder into the case if you have issues with running out of powder space in the case.

I did a load density test and was able to easily get 43.5gr non compressed load seating that bgr to a COAL of 2.700". I vibrate the powder down by cradling the brass on the top of a running Lyman Pro vibrating brass cleaner (old reloading trick shown by the guy who got me started in reloading). Works great.