Powder for loading down 7mm RM

A

aletheuo

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The best all round powders for the 7mm remington magnum appears to be rl 22 but I would like to load it down to 7-08 up to 280 velocities so I am wondering what you think is best for that in a 160 grain (speer hot cor).

Can I use rl 22 to load down to min of 2500fps or is it dangerous because it's so slow? If you think it's ok - where do you think I should start? Richard Lee Modern Reloading lists starting load at 59.5 grains or rl22 @ 2849. Maybe someone with quickload can run the data? 2500 to 2700fps in a 160 and rl22.

Aleth
 
4895 of either breed, is very accurate powder for loading lighter loads. It burns even and clean at reduced loads.
I would look up a maximum load of 4895 for your rifle, then drop back, maybe 20% to try it, and go from there.
 
I would do the starting load of 4350 for 7-08 speeds, or the max load for 7mm Rem Mag manual data if you want 280 speeds :D
 
168 sierra Match King BT (+-.1 gr)
57 gr IMR 4831 (+- .01 gr)
2608 fps
2582 fps
First group >2.5" cold barrel
Second group >1.0" warm barrel
@100 yds
Temp 4 C
Wind > 5 km
Bar NA

Driller
 
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todbartell said:
I would do the starting load of 4350 for 7-08 speeds, or the max load for 7mm Rem Mag manual data if you want 280 speeds :D
Click to expand...

Yeah, I have done the imr 4350 thing - went 55 grains (about 2700 - no chrony) but I would like to bring it down and little more but of course there's the whole "I don't like detonation" thing with 4350 - plus I only have a scant amount in the can.

As to the 280 speeds, it's actually kinda fun working my way down and knowing it's getting safer as I go (in using 4895, rather than 4350) rather than trying to wring the most out of it. If I wanted to do that I'd buy a 7-08, or maybe the stupidly sensible 260 remington. :D Instead, I have my magnaphobic's dream - the multipurpose 7mm RM. It's a 7-08, 280, 284 and a 7 RM all in one package. :cool: Might not be quite as efficient with powder as the smaller cases but it'll only cost me $10/year extra to feed it.
 
Max for a 160 grain bullet with RL 22 is 65 grains at 2976fps. The starting load, based on dropping by 10%, is 58.5. Doubt it'd be anywhere near 2500fps. Going below minimum is as unsafe as going above max.
If you want less felt recoil, use a lighter bullet. You still won't get .280 Rem or 7mm-08 velocities, but it won't hammer you as much.
 
I doubt 4350 would detonate unless you were way down in the charge below 10% of max or more. I chrony'd a load for a guy a couple weeks ago, 60 grs IMR4831 with 150 gr bullet did 2850 fps.
 
ok - so let's talk 4831 here. I'm beginning to suspect that Modern Reloading's claim to "highest velocity listed first" is a bit of bunk. And then there's this:

Source: Modern reloading 2nd edition
150 grain jacketed: imr4831 min 49.8 @ 2449, max 62.0 @ 2940 (57kpsi)
160 grain jacketed: imr4831 min 57.7 @ 2753, max 60.2 @ 2860 (56kpsi)

Source: Speer #10
145 grain: imr4831 min 59.0@2920, max 63@3081
160 grain: imr4831 min 58.0@2689, max 62@2979

Hodgdon Data Centre:
150 GR. NOS PART IMR 4831 58.0 2758 51,500 PSI 62.5 2925 59,400 PSI
160 GR. NOS PART IMR 4831 57.0 2707 50,600 PSI 61.0 2858 58,400 PSI


What is up with Lee's minimum load there (in bold)? Is it safe? Will the powder burn completely/cleanly?
 
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Please don't get Hodgdon 4831 and IMR 4831 mixed up or think their data's are interchangeable, as they are two different manufacturer formulas. The older the Load Book generally the hotter the recipe as in the Speer #10 reference. I can’t verify your newest lee 2nd edition data with out a reference but suspect a typo error at 49.8 at 2449 fps grains, but I have another sierra 160 recipe starting at 51.7 grains @2500 fps.
The loads listed may not rack a self loading bang stick, or may have a possibility of a squib in some barrels.
Most of the data are general start points are for common firearms for common manufacturer recipes and vise versa.
Unless you’re the U.S military wanting to propel a VW Beetle a distance of 26 miles and still be super sonic, it not that difficult, until you push the limits outside the normal data.
Diligence vigilance and take more care with compressed or wildcat loads but do have fun.

Driller
 
If it's below any newer book minimum I don't like it in the 7mm Mag ( the only REAL mag. the 7mm Rem Mag). Seems to be a bit twitchy in the pressure department sometimes on the higher end, God only knows why, so I suspect it can also be a little unpredictable on the low end, more than any other belted mag. If you want 7-08 velocities, them why not do yourself a favor and get a 7-08? As far as loading "up" to .280 speed goes, we'll let that slide...
 
No mix-ups on H and IMR - I triple checked the data... it says what it says. So, yes, it could be a typo or just old data chucked in there from before lawyers had their ways. I am using imr 4895 just to be safe, however.
 
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