Well I've put up with R-22 and R-19 for long enough. I got lured to the Allaint powders by the spectacular velocities and good accuracy. I just can't deel with the 50-150fps difference in velocity from hot to cold any longer. This has created 3"-5" POI changes at 300yds. I'm looking for a powder that will do 3300fps w/ a 140 TSX. The above mentioned powders easily did it in my 26"bbl. I was hoping to obtain this with an Extreme Powder as I've heard good things bout their temp sensitivity. I can get 3200ish with quite a few powders, but with the big 7 I like to wring it out. Thanks in advance, Brett

Actually my last lots of r-22 and r-25 were much less temperature sensitive than previous lots.Perhaps they have changed the formulation recently?

I have been a handloader long enough to se that most manufacturers have tightened the specs of their products whether bullets or powders.

I have seen 6% varaiation lot to lot 25 years ago reduce to 2% these days so it is apt to remember that this is the sort of improvement that does not require marketing, as it would not be healthy for sales relating to older stock still in the market place.

Could you imagine the barrage of inquiries by the consumer regarding lot numbers associated with the changes?

Keep the Chronographs turned on and check everything...often.

AGW

Try IMR-7828 or H-1000. I'm useing 7828 right now with 160's and getting over 3000fps out of a 24" BBL.

Jamie

IMR 7828 is about as close to R22 performance I've been able to find in some Weatherby Mags, 7RMs, and in 25-06. I never had great accuracy in my 7RMs with IMR7828 but, I can say it will give you R22 velocity from my experience.

BTW, I don't buy into the extreme claims. Every powder I've tested in extreme elements varied from hot to cold, even big H.

Good Luck

Reloader7RM

First one I would try would be 7828 as well, I've used it for my 7 RM's and Mashburn for a long time and it is day in and day out my go to powder.

Second choice would be H4350 or IMR 4350, it'll shoot well but most likely won't quite get the speed as 7828. But it will give you plenty of speed.

Good luck

Dober

7828

I found AA3100 shot really well out of my 7 mag. Can't say it was the fastest but it was the most accurate....

hunter-I am curious as to why the need for 33 instead of 32?

Thx

Dober

Mark- I've just always ran my 140's to 3300fps and I know my holds out to 500. I just don't see the point of a 26" 7mag if I'm not going to push it hard. Plus it's always been so simple to achieve I guess it would feel like a step backwards to back it off. No real need, just want. Brett

ya know, I had a younger guy over here that wanted me to do some loading for him, with a 160 grain TSX in a 7 Mag.. he had read all of this info somewhere on it, and wanted to get the most velocity possible out of it, for the longest range...

So I did so, and actually pumped it up to 3300 fps for him, telling him his case life would be about 2 reloads.. and that the pressure was over SAAMI specs, but that his Ruger 77 would handle it... However, he was not real happy about the accuracy...

So after him playing with a lot of stuff he had read, he finally came back and asked me for what my recommendations were... I showed him that learning to use the features on his 4.5 x 14 Leupold that he could do without 3300 fps...for ranging his shots out there... he learned that...

Then I did him an older book load using IMR 4064, for an MV of about 2950 or so...that yielded him dime sized groups at 100 yds...

He was quite happy with that, even if he wasn't using one of the trendy listed slower powders...

I see your point Seafire, but 3300 with a 160 is not really comparable to 3300 with the 140's. Brett

P.S.-wow, I'd be a little worried about pressure in that one.

Well you know how you can't seem to tell these younger guys with Magnumitis a darn thing.. they have to learn it on their own...

The funny thing is, he thought he needed this for Blacktail...

When he asked what I was using, I told him a 22.250....just to make a point...

Now he is thinking he needs a 358 STW for Elk....

he will eventually learn..

ok

I honestly can't imagine a 7 RM running a 160 @ 3300 without freezin things up.

I've done lots of foolish and crazy things in my life but I would never once even consider doing that.

Dober

Thx was just curious.

Try 7828 and see how it goes.

Of course the flip side to this is that with the loner 26" tube you could get to cettain speeds with a bit more ease than you could with a 24" and so your load would be breathing a bit easier.

What do you like to use for a LRF?

Also what part of Spudsville do you hunt? North or south?

Gracias

Dober

Mark,

We tweaked it, and it did chrono that...I was using some Weatherby Load data and we worked it up.. it didn't lock up the rifle, but as I said, brass life was short.. and accuracy was crap...

This is what he wanted.. despite my recommendations against it..

But some people just have to learn for themselves...

I am sure we were running in the 75K psi range or more....

I told him I wouldn't shoot it.. and some of you who know me know that I experiment.. but that was beyond my reasoning....

But accuracy and reality finally dawned on him....

But I did tell him no more loading about some load he read about, and something he thinks we should be able to do..

the only real reason I am loading anything for this guy, is that his dad is a retired Marine and Vietnam Vet, who can't handle recoil anymore since he had to have a heart bypass.. So I load up his 7 Mag at no charge... last year Dad's load was 35 grains of IMR 4198, with a 139 grain Hornady...

The "kid" he is 35 yr/old.. just tags along with his dad...hoping to get some free reloading done...I originally am loading for his dad, at no charge since he is a Marine Vet, from Vietnam days...

I would never consider loading a 7mmremmag to produce 3300fps with a 160gr bullet even to teach someone a lesson.

Mark- I'm currently using a Cabela's CLR1200 but not too impressed so a Leica is next on the list. I hunt all over the state but am much more familiar with the south-western portion(units 32, 32a, 33, 34, 35, 39, 40). Appreciate the help, Brett

In the 7mag, I found H4831 S/C Extreme gives within 50 fps of RL22 with 140-150 grain bullets. Very small extreme velocity spreads as well.

Other powders may give a wee bit more velocity, but I like what I see at different temperatures with it.

Norma powders are now available again and MRP & MRP II are supposedly temp stable.

In all cartridges that I've used MRP in over the years, the load data and performance has been the same as RL22.

Besides that grains are more uniform and it meters better than RL22.

I've managed to keep a small supply over the years for my 270s, 280s & 338's.

I don't shoot my long throated 7mag enough to go to the effort of changing from RL22 but I strongly suggest you give it a try.

If you do, let me know what happens.

MM

I just loaded up 28 rounds of Retumbo from 70-73 grains in .5 grain increments with the Barnes TSX 140gr and CCI Magnum Primers. I haven't been to the range yet.......Is there any reason that no one is using this combination? I thought Retumbo was the most accurate powder they tested.

Thanks,

I've never worked with Retumbo......let us know how it performs for you.

MM

50-100fps seems bit small to triffle over for a hunting load, but I understand pursuit of perfection. I know of few powders not somewhat affected by cold, but a few are far less affected by heat. Even the Hodgdon powders lose a bit of velocity in cold weather, they just don't get as spunky in hot weather. YMMV on that.

For me these days, whatever R-19 and R-22 will do, VV-N160 and N165 will do as well or better. I aint tried the N560 yet but plan to. 3300 is doable in a 24" 7mmRM with 140s...if your gun will do it, N160 will do it smartly. Consider it a tad faster than R-19, but a tad slower than H4350. Its "personality" changes dependant on case size. A buddy of mine actually has used it with R-22 data in his 7mmRM, but in smaller cases it seems a tad faster. Screaming hot velocities every time I use it though!

I like Alliant's RL25 for bullets 150gr on up in the 7RM, usually gives better accuracy and higher velocity than RL22. I just worked up a RL25/150BT load for my 7RM. Under a .5" at 3200fps using a 25" PacNor SS:


Will re-chrono this load when the weather cools to see how much velocity loss occurs.

MtnHtr

Montana Man,

Will do.

Ty at Barnes recommended the powder so we will see how it does. Barnes recommendation of IMR 4831 for the 300WM 168gr TSX worked out well for me today with a little over .25" group.

All the IMR powders are good performers........only problem is that they are a bit more temp sensitive that the Hodgdon, Ramshot & Norma lines, and RL22, but where you're at, prolly doesn't matter.

IMR4831 is just a tad faster than H4831.

Here's link to a good chart for comparing burning rates of powders easily.

Powder Burning Rates

MM

I'm using it. Settled at 73.5 grains, which shot around 3215 FPS with the first lot I used. The new lot is going about 50 FPS slower, but to the same point of impact, and both lots shoot just under an inch.