Thoughts, fellas?

I'm loading my 7 Rem Mag with 162 moly A-max's in front of 67.0 grains of H-1000 and getting excellent accuracy (.5 MOA). Although accuracy is my primary goal with this load, I originally wanted to move them at around 2900 fps. Unfortunately, 67.0 grns puts me at ~2745 fps. 68.5 grns (the max I've tried and chronographed) puts me at ~2750 fps... I was considering trying a slightly faster powder, as I'm wondering if I'm just running out of barrel. I'd like to keep the load density up above 90%, though. Thoughts, suggestions?

My Hornady book shows the 24" barreled 7MM Rem Mag using a max charge of 68.5 grains of H-1000 on a 162 grain A-Max bullet yields a velocity of 3,000'/sec. The pressure is not listed.

Alliant lists a 160 grain bullet with 65 grains RL22 gets ya 3,075'/sec and 58,600 PSI

70 grains of RL25 yields 3,049'/sec and 58,100 PSI. with the 160 grain bullet.

I'd try RL22 and see what happens.

If that don't help you can get a 7MM STW chambering reamer and open it up a bit.

I like IMR7828 in my 7mag. The new 7828ssc will allow you a bit more powder w/o over compression. It's also one of the most accurate powders I've tried for heavy bullets in the .260, .280 & 7mag.

If going up 1.5gr gains only 5fps, you may not be just running out of barrel, but running out of luck. You've hit the point of diminishing returns. It doesn't matter what anyone else can do in their 7Mag, every barrel is different. My only suggestion would be to work up a load without the moly and gain a little more pressure. Might be worth a try.

quote:

Originally posted by fredj338:
I like IMR7828 in my 7mag. The new 7828ssc will allow you a bit more powder w/o over compression. It's also one of the most accurate powders I've tried for heavy bullets in the .260, .280 & 7mag.

I couldn't have said it better. I too like IMR 7828, but am partial to VV-N160 and Nosler Partitions weighing 160 grains. It is this latter powder that put my 7m/m over the 3,000fps mark, something that H1000, RL22, and the 4831s wouldn't do for me.

You should definitely look at R22. It is a very fine powder in the 7RM especially if you want top velocity w/ safe pressures.

W/ 160 Sierra BTSPs over 66 grns of R22 I'm getting 3080-3100 fps @ 12-15 feet from muzzle.

R22 is my favorite powder w/ 150s, 160s, and HDY 162s. I have had good luck w/ 140s over H4831.

Haven't tried 7828 in a 7RM but, it should be good as well, it sure is a screamer in my 7WEA.

Good Luck!

Reloader

Forgot.... Rem. 700 24" factory tube for the above velocity.

Have a Good One!

Reloader

quote:

Originally posted by tmoore4627:
Thoughts, fellas?

I'm loading my 7 Rem Mag with 162 moly A-max's in front of 67.0 grains of H-1000 and getting excellent accuracy (.5 MOA). Although accuracy is my primary goal with this load, I originally wanted to move them at around 2900 fps. Unfortunately, 67.0 grns puts me at ~2745 fps. 68.5 grns (the max I've tried and chronographed) puts me at ~2750 fps... I was considering trying a slightly faster powder, as I'm wondering if I'm just running out of barrel. I'd like to keep the load density up above 90%, though. Thoughts, suggestions?

Yes. I found that among the latest powders using Nosler Partition 175-grain bullets in my 7mm Rem. Mag. w/26" barrel, I could get no more than 2900 FPS with acceptable pressures using RE22, but could safely achieve over 3000 FPS with this same bullet using IMR 7828. Of course, ALL RIFLES ARE INDIVIDUALS, and some may not be able to do this.

IMO, if you are only able to get velocities in the 2700 FPS range with a 162 grain bullet, you might as well be shooting a 7X57mm Mauser, 'cause the 7X57 will do as well as that!

I appreciate the help guys. I actually have some RL22 that I original bought to load 120 gr V-maxs, but never got around to it, so I'll try some of that. If that doesn't do it, I'll give the 7828 a try. I hate to mess with a load that gives me this kind of accuracy, but I guess the pursuit of the PERFECT load is really what loading's all about... Thanks fellers

tmoore, you should have good results w/ RL22, it's a bit faster than IMR7828. It's too slow for your 120gr though. H4831, IMR4831 or RL19 will probably get you higher vel. w/ the lighter bullets. BTW, I use IMR7828 in my 23"bbl. .280 & get 2825fps+ w/ a 160gr bullet.

quote:

Originally posted by tmoore4627:
... I hate to mess with a load that gives me this kind of accuracy, but I guess the pursuit of the PERFECT load is really what loading's all about...

Hey Tim, Just write your old Load down and you can always go back to it if need be. That way you won't mess it up at all.

I never could get IMR-7828 to shoot in any of my 7mmRemMags, but as you can see from the posts it works very well for other people. And the RL Powders which seem to work great for EVERYONE else always had unusual Pressure variations for me.

I got one of the Hodgdon paperback Reloading Manuals as a door prize at a Banquet last month. It seems to think the new "Retumbo" is the best Hodgdon Powder for the heavier bullets in the 7mmRemMag. I've not tried it, but it is on my list of things to do.

IMHO - they should have named the round the 7mm belted and left the magnum off the name. It is a good round but so many people expect very high velocities with it which are seldom achieved.

IMHO Old elk hunter is correct it does not have
much advantage over the .30-06 with 180 grain
bullets.I shoot one though and dont have any complaints either but I feel it is best
with the 175 brain bullets as the sectional density is outstanding.For the case size it is not much ahead of the .270 win. The 270,.3006
and the 7mm rem mag are not much different i own all 3 calibers and 3 of some of them.
Make it shine and use the heavy bullets with it.

quote:

Originally posted by Old Elk Hunter:
IMHO - they should have named the round the 7mm belted and left the magnum off the name. It is a good round but so many people expect very high velocities with it which are seldom achieved.

First off, let me state that it is not my intent to start an arguement.
Second, I believe the 7m/m Rem is a victom of its own success. It is a "johnny-come-lately" in the gun world, and along with its rise in popularity was the avalibility of affordable equipment like chronographs. Given that folks thinh the big 7 is a fraud in the velocity department, so too can that arguement be made for all the hype that manufacturers brought along with the new wondermags. One need look no farther than Weatherby's creations to find this. Roy himself would have been doomed to failure had it not been for IMR 4350 in post-war America. Moreover, his cartridges have only come into their own with the availability of powders in the burning range of 4831 and slower, and that holds true for any cartridge with the capacity to hold 65+ grains of powder.

I had problems getting expected chrono vel. in my 1978 Ruger 7mmRM.factory bbl so I had it rebarreled and what a difference.I don't know how old your rifle is, your problems may be a shot out bbl

quote:

Originally posted by cal30 1906:
IMHO Old elk hunter is correct it does not have
much advantage over the .30-06 with 180 grain
bullets.I shoot one though and dont have any complaints either but I feel it is best
with the 175 brain bullets as the sectional density is outstanding.For the case size it is not much ahead of the .270 win. The 270,.3006
and the 7mm rem mag are not much different i own all 3 calibers and 3 of some of them.
Make it shine and use the heavy bullets with it.

We all know Jack O'Connor's hangups regarding the .270 Win., but he once wrote that he could see little, if any, difference between the killing power of the .270, the .30/'06, or the 7mm Rem. mag. vs the 7X57mm his wife used to shoot. He was probably close to correct on this evaluation.

I recently acquired a .30/'06 again after many decades of using other rounds, and am amazed to relearn just how outstanding the old round still is..... 100 years old as of next year!!

quote:

Originally posted by tmoore4627:
Thoughts, fellas?

I'm loading my 7 Rem Mag with 162 moly A-max's in front of 67.0 grains of H-1000 and getting excellent accuracy (.5 MOA). Although accuracy is my primary goal with this load, I originally wanted to move them at around 2900 fps. Unfortunately, 67.0 grns puts me at ~2745 fps. 68.5 grns (the max I've tried and chronographed) puts me at ~2750 fps... I was considering trying a slightly faster powder, as I'm wondering if I'm just running out of barrel. I'd like to keep the load density up above 90%, though. Thoughts, suggestions?

I/m thinking three thoughts:

1. Your rifle will shoot 1/2 MOA as it is. A hit with a .22 Short in the right place is better than a misplaced shot with a 577 Nitro.

2. You probably didn't buy a 7 m/m Mag as a BR Queen anyhow.

3. What elk will ever know the difference between your current velocity and 3,000 fps?

Be Happy! Shoot that sucker 'til one day when you tip it down a bit the rifling just falls plumb outta tha barrel!! [G]

tmoore, here's another thought. You are shooting moly coated bullets which reduce bore friction. Try increasing your powder charge 1/2gr at a time until you reach pressure signs. Then back off 1gr & shoot for groups. Speer manual shows 69grH1000 under 160gr bullet. I've found MC bullets require more powder to get them up to speed.

I dont know what you people are smoking that think a 175 grain in the 7mm mag doesn't have much of advantage above the 30-06 180.

175 grain 7mm mag 3055 fps

180 grain 30-06 2700-2800

Only couple hundred fps however, almost a thousand pound more knockdown power. Like apple's and oranges.

Scratch

Thanks for the suggestions guys.
Hot Core--I've got that load MEMORIZED, just a figure of speech.
OEH--I don't expect or even want super-high velocities, but I would like to push them a little closer to the round's potential, as otherwise, as cal30 suggested, there's no advantage over other "lesser" rounds.
Rob1SG--It had better not be shot out! I've only got about 500 rounds through it, much of it factory!
Canuck--You're absolutely right. I just can't leave well enough alone!
Fred--I looked back and actually saw I had tried as high as 70 grns of H1000 with no significant (or at least reasonable) increase in velocity.

Thanks again fellas