Sniper Country Duty Roster collective wisdom


Reloading compressed loads:


Reloaders,
Will I get a pressure increase if I have a compressed load?? I started loading 140MKs for my new 260 and they take up a "LOT" of the case and loading them sounds like I'am crunching rocks in the case. My main concern is with the Reloader 22 I have heard this powder is touchy, any thoughts??
Pat <mrbullet@hotmail.com>
USA - Wednesday, January 13, 1999 at 15:06:40 (EST) 
Compressed Loads ...
Pressure depends on many things - some powders in some cartridges can do fine with a compressed load (pressure wise) you need to know the dope on your particular cartridge / powder / primer / neck tension / bullet jump / bullet weight / etc / etc.

I can tell you that even if a comppressed load does not send receiver parts flying - more accurate loads are usually built around the very thin line of 98- 99% case volume - under the bullet base. Many good handloaders will "tap" the loaded cases on the table before pushing the bullet down just to make sure the powder settled below where the bottom of the bullet will end up. Just like a box of corn flakes - powder can settle in the case about a million different ways. If you are loading with enough powder to pretty much fill the case some of the thrown charges may end up getting compressed and some may settle just right - consistency will suffer based on this chance settling of powder. The tubular powders 4895 - 4064 and even Varget will settle different each time. If you push a bullet on a powder charge that just happens to stand tall in the case you might compress it, and it may compress in such a way as not to "settle" down through normal handling later on.

J.D.
J.D. Hicks <hicks@zso.dec.com>
Seattle, WA USA - Wednesday, January 13, 1999 at 22:40:39 (EST) 


Compressed Loads...

I have to say one more thing about pressure in general. One can get excessive pressure from more than just too much powder. If a particular load is at or near max, any change in components or loading technique must be approached carefully.

Heavier brass has less internal capacity, full length sized brass vs. neck sized brass can change internal capacity, hotter - different lot of primers, thicker necks on same kind of brass, different neck sizing dies or full length dies that result in a tighter neck, tighter crimp if you are actually using any crimp at all, a general load of crap inside the neck can result in a heavier grip on the bullet just like a crimp. Bullets seated our farther or some different bullet style / shape of the same weight. Hotter ambient air temperature with a sensative powder, stop using moly. Differnt lot of powder - tumbler crap left in the case.

Get the idea?

J.D.

J.D. Hicks <hicks@zso.dec.com>
Seattle, WA USA - Wednesday, January 13, 1999 at 23:00:51 (EST) 


Pat: my opinion is that nothing drastic is gonna happen on the .260 unless you are actually crushing powder grains. Just to pack it don't make much real pressure change at that point othere than the added powder.

B.Rogers <brogers@elkhart.com>
USA - Wednesday, January 13, 1999 at 23:42:49 (EST) 


JD and Bill,
Thanks for the comeback on the compressed loads. I wasn't worried about the normal compression of powder, were talking a bullet going three quarters of an inch down into the powder charge. The powder I am using isn't listed in my loading data. It is listed for the 7mm-08 and I took the light load for the 140gr in the 7-08 to come up with this load in my 260 maybe I am wrong for doing this also any thoughts??
Pat <mrbullet@hotmail.com>
USA - Thursday, January 14, 1999 at 09:31:16 (EST) 
J.D. I like your post about compressed loads. I use 4064 and 4895. What I have found is if after I drop the load into the case I tap the case a few times, the load will settle. I think this has helped group size. I know it has helped with ave. deviation. Extreme spread over ten rounds, out of my PSS, Fed Brass, Fed Match Primers, Sierra 155 Palma's and 45 grains of 4064 is 26fps. That is very good. So there is something to this. Dump and run charges don't even come close. I think you have something.

Mike M. <DMMDNLN@AOLL.COM>
Calif USA - Thursday, January 14, 1999 at 10:43:20 (EST) 


Pat; you must be wrong by doing that cause I'm sure that's just exactly what I would have done. Long as your groups are good and your pressure is manageable I'd shoot that load specially is it shoots better varget.

B.Rogers <brogers@elkhart.com>
USA - Friday, January 15, 1999 at 05:07:40 (EST) 


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