I was refining my loads with IMR 7828 and H-1000 and found that with a 150 grn SMK I am getting a great group with 80 grns of H-1000 at 3202 FPS and a really great group with 78 grns of IMR 7828 at 3242 FPS.

The H-1000 burns cleaner and has a smaller cut than IMR 7828. The IMR will produce a better group and I am going to have to tweak the H-1000 to get it to tighten up.

I don't think 40 FPS and two grns of powder would be a deal breaker. I shoot Hodgen powders for my .270 and 257 Roberts.

With that all said is one powder overall better than the other or is it a Chevy/Ford thing.

Mine likes RL-25.
What primer are you using, I gained 75 FPS when I switched to the federal 215 M.
I have had a tough time finding the federal match primers , but the velocity is about the same with the standard 215s.
I use the 160 grain acubond and bet about 3200. H-1000 has given me some startelingly tight groups too.
Seems to me since you are shooting match bullets I would go with the most acurate powder.
Clean burning is great, but you gotta clean it anyway.
Witch hodgden powder do you like in your Roberts. I have done prety well with H-414, But good old IMR-4350 is really good.
...tj3006

I am using the CCI magnum large rifle primers for the 7MM STW. The IMR 7828 will be the powder of choice for the 150 grn SMK, unless I can get the group tightened up with the H-1000. The H-1000 will get the nod for the 140grn Acubond.

I do not seem to get the same velocities from my STW as most of the other guys. I'll take accuracy over velocity though any day of the week just greedy and want both. LOL

I am using H-4831SC for the Roberts because that is what I had at the time I started loading it. It shoots great with 49.5 grn and a 100 grn Sierra GK.

In my 7mm's of various case capacities, I find IMR 7828 to be an excellent powder, along with H4831, RL 22, and Norma MRP......

My experiences with H1000 have convinced me that it changes position on the burning chart depending upon which case it is used in, and in general, it burns faster than charts indicate. I also think it suffers from the same lot to lot variations that the Reloader series does. Some swear by it; I swear at it. Seems to me your troubles would be solved with IMR 7828SSC.

If possible I'd talk you into using 160 grain bullets at a minimum as they are the ideal bullet in .284" diameter and you have the case capacity to drive them fast. Like the 30 calibre family, 7m/ms are blessed with a plethora of bullets and 160s are the cats meow; heavy without the aerodynamic penalties of the 175 grain round noses.

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If possible I'd talk you into using 160 grain bullets at a minimum as they are the ideal bullet in .284" diameter and you have the case capacity to drive them fast. Like the 30 calibre family, 7m/ms are blessed with a plethora of bullets and 160s are the cats meow; heavy without the aerodynamic penalties of the 175 grain round noses.

Yes, I agree entirely.

The problem with lighter bullets is, not to many, if any, are designed to work correctly with impact velocities above 3000fps, indeed most bullets can come appart and fail to penetrate well if they impact above 2700-2800fps.

This has the potential to cause problems with the closer range shots, until the speed of the bullet has dropped off into its design range.

The 160 grainers or heavier, have an advantage here, in that they usually start out slower. They also will have a better BC and SD, meaning they will be less resistant to wind, retain their velocity better and penetrate better as well.

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The problem with lighter bullets is, not to many, if any, are designed to work correctly with impact velocities above 3000fps, indeed most bullets can come appart and fail to penetrate well if they impact above 2700-2800fps.

Just use a 140gr tsx or mrx and don't worry about it.