How to load rem mag with 860?

[maxF]

I want to do some shooting with my new 7mm rem mag cheaply so I bought some surplus 860 and rem core lock, and Hornady amax bullets. I'd like your ideas on if I can extend the barrel life by shooting milder loads say 2500fps (140gr). Would casting lead bullets be easier on the barrel? I'm thinking of putting 5 gr. of some 2230 under say 50 grains of 860 with a win. mag primer ?? I have a savage with 24" thin barrel (the cheap package gun). I can tinker with grain amounts to get an accurate load I figure and would need to be MOA I think to get some accuracy at longer ranges. I'd like to get out to 600+ yards and 2-3 moa would be harder to tell, I would think. Any ideas?? thanks-max

[Ricochet]

Any amount of WC860 you can stuff under a 140 grain bullet in a 7mm Rem Mag will be a relatively mild one pressure-wise. Takes a 175 grain bullet to max it out. I haven't yet tried (just got a Lee mould recently), but I suspect you'll find it tricky to get good accuracy with a cast boolit at 2500 FPS with that 9.5" twist, and WC860 doesn't lend itself well to much-reduced loads. I'd fear detonation if you go down too much.

[maxF]

I'm assuming a 168 gr cast boolit would be better than a 130 gr (lee) for a long range shot? Would the 130 gr work with a magnum case filled with 860? And what would you recommend (grains of 860) for a 1700 fps load with cast 130, 168 ?? Would I need to gas check a 1700 fps boolit? The 2500fps I was referring to would be with a jacketed 140g to hopefully lower the wear out factor for the barrel as oppossed to the 2900 loads typical for a rem mag.

[Ricochet]

I think (because these are not loads I would experiment with) that the full case of WC860 under a 130 grain cast boolit will be way too hot for good accuracy. (As in fast, the pressure won't be dangerous.) And I think you'd have to reduce it so much to get down to 1700 FPS that you'll be in the low case fill range where you have poor and inconsistent ignition with a risk of "detonation," or "SEE," that can blow a rifle up. There are better powders for cast boolits in magnum rifles. I've done a bit of experimentation with promising results using IMR 7383 for lighter charges with cast boolits in the .300 Weatherby Magnum. Haven't gotten around to trying cast boolits in my 7mm Rem Mag, I only recently got the Lee 130 grain mould. But moderate charges of 7383 are what I'll start with, because I have it handy and have had encouraging results with it in the .300 Weatherby. Lyman lists loads with a number of standard powders in their manual, going up to over 2700 FPS, but says accuracy was poor past 1700 FPS, I believe.

[Jim]

Max,
About 300 years ago, Buckshot tried to overload with 860. He posted that all he accomplished was bulging the case. Fille the case TO THE MOUTH, rake it off and compress the snot out of it with your boolit and that's 'bout all you can get out of it. Now, where the sweet spot is, is yet to be determined. Oh, BTW, it helps a bit if you kick h311 out of it with a large magnum rifle primer.

[Ricochet]

I have actually been able to get to sticky case pressures in my Winchester M70 7mm Rem Mag by packing 80 grains of WC860 under 175 grain Hornady seconds, crimping tightly in the cannelure with a Lee FCD, and shooting in hot summer weather. (In freezing weather they shot great at 2960 FPS from a 26" barrel.) You're not going to be able to max out the pressure with any load of that stuff that will fit under a 140 grain bullet.