7mm Rem Mag H1000

[bteate]

I tried some H1000 in my 7 RM with better velocity, but so-so groups, not what I expected. Once again, odd velocities with the lighter charges averaging higher velocity than 1gr increase in powder. Started seeing a little pressure @ 72grs.

velocity avg for:

71gr-2953

71.5-2934

only one shot with 72gr @ 2950

What's the deal, Doc, JD338, Pop, anybody got any suggestions? If I cant get something figured out soon, I'm dropping back to 140gr AB and IMR4350 load, I know it rocks. I sure do like that 160gr AB, though.

 

[CAhunter]

Sounds like 71gr is the peak of pressure. Have you tried IMR 7828 or RL22?? The 160gr should be a great bullet in your rifle!

 

[spires5d]

In the past i've loaded up some Nosler 160 PT with 58 gr. of IMR 4350 and got 2943FPS out of them with my 7MAG. My book also shows loading 160 gr. PT'S with IMR 4350 powder at 60 grains to acheive 2998 FPS. You should be able to load the 160 AB"S with this load.





7Mags forever and a 30 cal. will "Slam Dunk Um"

 

[bteate]

I've tried RL-22 with low velocity (below 2800 fps w/63.5 grs) I'm going to step it up some, but I just tried H1000 because I've had real good results in a 300WM with it.

 

[SJB358]

Give RL22 a try in your 7mm Rem Mag. It has worked pretty well for me with the Accubonds. Start at 63gr and work up. I would think you should get about 2950-3000 at around 65-66gr. Mine is very accurate with the AccuBond and really is a flat shooting load. Scotty

 

[DrMike]

160 grain bullets are about optimal for shooting from the 7mm RM. 71 grains of H1000 is pretty near a maximum charge. Clearly, in your rifle the charges you threw are reaching peak pressures and you are not getting any more velocity as the pressure curve is extended. You are tickling the dragon's tail at this point.

I'd recommend focusing on a somewhat faster powder. As has been mentioned already, RL22 is as fine as you can go for many loads. Recently, I've had some very good success with MagPro and H100V. In fact, with a 160 grain PT and 59.5 grains of H100V, I'm getting 2983 +/1 1 fps and groups of 0.59 inches, and this from a rather old rifle that has had several thousand rounds through it. There is still room to increase this charge by about a grain, so it is by no means a maximum load.

 

[SJB358]

Mike, is 100V an Extreme Powder. Those are great speeds your getting. Seems like there has to be something out there that can break the magic 3000FPS barrier with a 7mm Rem Mag other than H870. I could do it very easily with that, but nothin else has done it for me. Not that I am complaining as 2950 is mighty close, but just wondering. Scotty

 

[DrMike]

Scotty,

I routinely break the 3000 fps mark with 160 grain Fail Safe and RL22 (~3050 at 64 grains and ~3164 at 66 grains). The groups open from 0.28 inches at the lower charge to 0.87 inches at the heavier charge. Likewise, with a 160 grain TSX and either 68 grains of RL25 or 67.5 grains of IMR7828, I'm right at the 3000 fps mark or slightly above. I have tended to settle for a slightly lower velocity on the 160 grain bullets. Actually, for this rifle I usually shoot 175 grain bullets. Speer 175 grain MT with a charge of 62.5 grains of RL22 yields 1/2 inch groups and a velocity of ~2900 fps. 61.5 grains of RL22 and 175 grain PTs give me ~2800 fps and 0.8 inch groups. However, my standard load for many years has been 175 grain TBBC and either 60.2 grains of WXR (0.44 inches and ~2800 fps) or 79 grains of H870 (0.48 inches and ~2950 fps). I've still got about 150 TBBC that I bought years ago from Jack Carter. Obviously, I'm parceling them out. Likewise, I have about six pounds of WXR and three pounds of H870 and are reserved for hunting ammunition.

 

[SJB358]

Rgr, that sounds pretty good Mike. I was wondering about it. Maybe my WBY is a slow one. I am at 66gr of RL22 and still at 2950. Again, I am not complaining, as I could probably go further, I was just wondering. 2950 will do everything 3000 will, just seems like the 7mm Rem Mag should make the 3K mark. I might have to experiment a little. I like the load I have, but I won't be using it anytime soon, so maybe I will try something else out. I guess I just miss the speed H870 gave me with 0 issues or pressures. My older M70 would break 3K with about any bullet and 79-80gr of H870. I just don't have alot left (2.5LBS) to really experiment too much with it. Plus, it was always really accurate toward the upper end of the velocity spectrum. Scotty

 

[DrMike]

H870 always worked best with a stiff charge. As you approached maximum the accuracy became more pronounced. This tends to be a general phenomenon for most slower powders.

 

[SJB358]

Mike, what is closest to H870 on the powder burn rate scale? Any of the Hogdon Extreme powders? Scotty

 

[DrMike]

Scotty,

Retumbo is the closest Hodgdon powder to H870. It would appear that 75 grains will be a compressed load, but it will give a velocity approximating a stiff charge of H870 (79 grains). Of course, Retumbo is listed as an extreme powder, as is H1000. The H1000 will be a slightly faster powder than the Retumbo.

 

[SJB358]

I may grab some Retumbo. I was always going to try it out in my 270WSM. RL22/IMR7828SSC really does good for in it though. I may give Retumbo a try in the 7mm Rem Mag. Scotty

 

[FOTIS]

As stated you peaked it. When velocity starts to drop of after increasing the load the barrel starts to decelerator the bullet due to friction.

66 grains of rl 22 for any 160 grain. That is where it is at.

barrel length?

 

[bteate]

Pop, it's a 26"- 9 1/2" twist. I'm going to start bumping up the charge on RL-22 in the next couple of days and see what happens. What is the possibility of a slow lot of powder? My loads of RL-22 did the same thing, increase charge=decrease velocity when a certain point is reached, but no pressure signs. The only difference is that the RL-22 was super slow (2763 fps @ 62) I'll let you know what happens with the increase charge of 22.

 

[Bruce Mc]

my go to load for 160 AccuBond is 74grs of H-1000 and it creates 3050fps or so. No pressure signs in my rifle. It consistently shoots one hole groups.

You might try toying with the seating depth. It can make a big difference in some rifles. My 7mm mag doesn't seem to be too finicky but my .257 roberts is extremely finickly with accubonds. The magazine in short in my 7mm mag Winchester model 70 so the bullets are seated way off the lands.

 

[DrMike]

bteate,

You can see lot-to-lot variations in burn rate as great as ten percent.

 

[spires5d]

Mike, sounds like you have had good luck with the 175 gr.s At the present,I'm loading Speer 175 gr. Mag tip with IMR 4831 powder at 59 gr. my old Savage 110 shoots them well at targets and also on deer. I've got 300 more of them to shoot,then I'm going to Sierra 175 gr. SP. Both 160 gr. and 175 gr. bullets shoot well in my Mag even if I'm a little under 3000 FPS. The deer don't know this.






7Mags Forever and a 30 cal. will "Slam Dunk Um"

 

[DrMike]

As I said, my go to bullet for years was the 175 grain TBBC. It shot consistently at 3/4 inch and gave me good velocities. I've taken many black bear and mule deer with that load, and a few elk and moose as well. I wouldn't hesitate to tackle any of these critters with either the 175 Partition or the 175 MagTip. Either will do the job when required. If I had invested time with the 175 grain Sierra, I have no doubt that it would work equally well. I generally focus on 175 grain bullets in my 7mm RM and use 160 grain ABs in my 7mm WSM. They are racing along at 3000+ fps and give me 1/4 inch groups. They have accounted for quite a few whitetail and mule deer here in the north. You are right that most deer can't really tell the difference between 2800 and 3000 fps.

 

[nodak7mm]

Doc, Pop and all summed it up. RL22 and yes, you are running it too slow. I have no prob with busting 3k and my starting loads w/RL22 are 65.5 behind 162 Amaxes. I got some 180 Bergers coming and with those I'll be looking at RL25..

Face it, the 7RM likes to run so push it to the redline.

Rod