R-19 powder or H 4350

[bruce moulds]

yes it can be used, but other slower powders will deliver more velocity at less pressure generally.
bruce.

 

[375 Ruger Fan]

4350 and re 19 are too fast burning for all but 100 gn bullets in the 7 mag if you want to achieve full capability of the case.
the 4831s are good for 120 gns.
imr 7828 was designed for 7 mag facory ammo, so that gives a bit of a guide for most used bullets in 7 mag.
re22 is a little faster than that.
h1000 might be a little slower?
the last 3 would be your friends.
bruce.

@bruce moulds FWIW, the Swift manual lists RL22 as having the lowest SD with the 160 gr SAF w/86% fill. It lists RL19 having the lowest SD with the 150 gr Scirocco w/ 88% fill and also the 175 SAF w/ 80% fill.

Question for you regarding any recipe with RL22: Is it preferable or at least ok to substitute with RL23? From what I've read, 23 is an improved and more temp stable version of 22. Appreciate any comments on this.

 

[bruce moulds]

just because that happened in a manual does not mean it will be the case in your gun.
many factors come into low s.d.
such things as primers, seating depth, neck tension can vary that.
the other question is , when does s.d. become a problem.
at hunting ranges, say out to 400 yds, it has to be a very big number to be noticeable.
also it does not follow that lowest s.d. is also tightest grouping.
as 1000 yds, or at least past 600 yds, velocity variation will show vertical.
i have never used re 23.
the chart i looked at showed it to be a little slower than re22, but a guy i know that uses it in a 7mm saum quoted figures that suggested it is faster burning.
bruce.

 

[Viral_SIGness]

I used RL22 with my 7 RM.

 

[Viral_SIGness]

Hornady data
150-154gr Bullets

162 grain

 

[bruce moulds]

there are so many things that affect grouping and s.d. that doing using a recommended load, powder, bullet, etc is almost self defeating.
fclass shooters work on this bigtime, as they shoot at 1000 yds a lot, and vert is their enemy.
things that affect s.d. include.
case capacity. different capacity boiler rooms produce different pressure/velocity.
anneal of necks. inconsistent anneal produces inconsistent neck tension with obvious results.
neck length and deburr. a same clean release of the bullet is required.
seating depth. a consistent start to bullet movement can be had by experimenting with jamming the bullet 5, 10, and 15 thou into the rifling. however this is totally unsuited to hunting.
so jump tests must be done, which might be limited by mag length.
then you can get great s.d. and bad groups!
when powder or bullet companies quote best s.d or group sizes, they fail to give full information.
e.g. are they using new brass or fireformed.?
how much jump to the rifling?
and so on.
there is only one way to work this out in your rifle with those components, and all factors must be recognized and dealt with for meaningful results.
then you need to recognize a realistic goal, taking all factors into account.
i know a guy who put tight groups ahead of ammunition mechanical reliability, and failed to have enough neck tension to hold his bullets well enough.
and another thing is not to start testing for s.d until your barrel has been fouled with at least 5 shots.
and an s.d. figure is meaningless for less than 10 shots.
how many time do you see some well meaning guy quote an s.d., only to find it is for 3 shots.
bruce.

 

[Pheroze]

@Pheroze I realize your comments about reloading for your Browning BAR in 7mm are about 5 years old, but was wondering what you came up with. Now that I am retired, I am slowly getting more and more into reloading. I have a BAR in 338 WM and it shot just about anything I fed it equally well. Remington Core-Lokt in 225 gr shot really well.

@Shootist43 got me going with recommendations on H-4350 and I've slowly added a few other powders (Accurate MagPro, IMR4831, Superformance, Alliant PowerPro 4000 MR and Ramshot Big Game).

I have a Ruger M77 in 7mm mag that I want to work up a good load for, using either Swift A-Frames, Nosler Partitions, Hornady SST or ELD-X bullets.

FWIW, my Montana elk guide shoots 7mm mag and reloads with 160 gr Nosler Accubond and 62.5 gr IMR 4831. He routinely takes out wolves and coyotes at 500 yards. This is from a Tikka bolt action.

Sorry I missed this. I have started using the app and it doesn't notify me like the browser version.

I never really got very far unfortunately. The rifle hasn't been used in years with my father not hunting anymore and my son prefers my Browning ABolt II.

Reloading for a semi-auto lacked some of the joy of sizing the case "just so".

 

[Pheroze]

I spoke to soon....what an odd coincidence. I was over at my father's today to help out. He told me to take the BAR. I forgot, he actually has two. He offered to let my youngest use/have them. So, I guess I should dust off the dies and powder. I am still unsure about reloads for a semiautomatic. I am more nervous about the brass failing because I can't minimize the stretch by sizing the case to the chamber.

 

[Bob Nelson 35Whelen]

I spoke to soon....what an odd coincidence. I was over at my father's today to help out. He told me to take the BAR. I forgot, he actually has two. He offered to let my youngest use/have them. So, I guess I should dust off the dies and powder. I am still unsure about reloads for a semiautomatic. I am more nervous about the brass failing because I can't minimize the stretch by sizing the case to the chamber.

@Pheroze
Cases shoulnt stretch anymore in the BAR than a bolt action unless it has got an oversized chamber or the cases have been sized incorrectly.
That's BAR from memory uses a rotary multi lug bolt head that locks up just as strongly as a bolt action.
Bob

 

[badsection]

Use what produces the best accuracy and what is available!

 

[Rule 303]

Powder temp sensitivity is more a worry in heat than the cold. In the cold pressure can be down and the bullet slower, different point of impact. Heat can cause over pressure and become dangerous.

Extreme cold (what temp range this is I do not know) can result in hang fires or powder not burning effectively. Using Magnum primers can help alleviate this. Powder companies should be able to advise what sort of temps their powders are reliable in. Even the coldest part of Australia is unlucky to make -15 so we don't have the cold temps you do in the Northern Hemisphere.