7 mm STW powder choice , Has it been Covered

[BLASERMAN]

I looked some what. Whats the best powder for a 7 MM STW
I am using one of richards 150 ULD RBB witha 26" Barrel.

 

[MagMan]

H1000 is where I'd start.

 

[abinok]

150s? h1000.. heavier... retumbo... though id probably suggest try both either way. I did /ubbthreads/images/graemlins/smile.gif

 

[dakor]

They really seem to like H-1000. I have tried Retumbo but had better results with H-1000. I even have used H-1000 with 140 class bullets with good results.

 

[.30-378]

H1000 is fine except H4831 (or SC) will do it about 110 FPS better and Retumbo is a dirty powder that will foul you up very quickly and create a sticky and dangerous bolt situation. I have some excellent 140 grain data if you would like to have it - 1000 and 4831.

Seeya.

 

[Blacktail2]

I have had good luck with H1000 and Retumbo.Both gave me good accuracy with 140 & 160 gr. The Retumbo gave a little more velocity with a little less presure.Also lower ES & SD.

 

[Ridge Runner]

I shoot H1000 with the 140's and wc872 in the 160's. US869 shows some promise as well.
RR

 

[drpbroun5]

.30-.378,
I would like to get your load data for both bullet weights with both powders. Thanks.
Paul

 

[.30-378]

These are at the maximum levels. The H4831 load was created by me before load data was published. I used some dead reckoning off of the 8MM Rem Mag. I also have gone back to H4831SC for everything and every weight from my
.25-06 Rem. through the .30-378s. An old reloader 27 years ago taught me the benefits of it and after some experiments, I kept going back. It is the powder for me. I blast my 150 grain Ballistic Tips out of the .30-378 guns below at a little over 3700 FPS. That said:

H4831 is 81.5 grains for a 140 grain Nosler Ballistic Tip
H1000 is 82.0 grains for the same bullet
H1000 is 80.0 grains for the Nosler Partition and
H4831 is 76.0 for the same bullet

All used Winchester magnum primers are trimmed to 2.84" with an overall length of 3.575". It might be obvious, but the cases are also chamfered and deburred. Sierra bullets in the same weights can be used as well.

Out of my 2 26" barrels, here are the average speeds from my chrono:

140 with 4831 - 3510
140 with 1000 - 3405
160 with 4831 - 3350
160 with 1000 - 3255

I haven't cracked a case (4 or 5 loads per case and they all seem to need to be cut back about .11" when done with sizing - been working with about 250 cases. Some 8MM-based cases and some STW cases.

One trick I also learned many years ago to create a good fit and and tight fit for uniform chrono speeds is to hold a bunch of bullets in your hand to create a sweaty situation. That sweat will lock-in and provide some very consistent pressure levels. As a sidenote, if you ever try to pull a bullet, you'll see the difference from those not locked-in.

Have fun.

 

[keithcandler]

I shot 83.0g of IMR 7828, Fed 215, Winchester brass out of my STW at 3350 fps. What ever you choose to do, use Winchester brass. Remington brass is very soft and you will reach premature high pressure loads loosing primer pockets.

 

[284STW]

Retumbo has been a proven performer for not only mine but a couple of other fast 7's as well. Just my experience. I haven't noticed fouling to be any different with retumbo than anything else. My gun gets cleaned religiously anyway...

 

[blygy]

My load was IMR 7828 79.3 grains with 215 primers. This was good for 3380 with the BXfb. I shot both 150gr Barnes X FB and 150gr Nosler Ballistic tips with outstanding accuracy..

Blygy