Compression Die for lyman/rcbs dies

[Muddy Creek Sam]

Howdy All,

Stupid Question Time. I just got my Compression insert from Buffalo Arms,http://www.buffaloarms.com/browse.cfm/4,3271.html , Came with no instructions. Anyone help a newbie reloader out?:oops:

Thanks,

Sam :-D

[August]

It should work in place of the bullet seating plug in the seating die.

[Jon K]

Compress the powder deep enough, that when the boolit & wad are added, you get your desired OAL. Start out with little to no compression and increase til it shoots best.

Jon

[NickSS]

What John K says is just about it. I bought an extra Lyman M die for my compression plugs for the different calibers I load. I start out figuring a load with no compression and go up from there until I find a load that shoots well. I always drop my powder through a 30 inch drop tube into the case before compressing the charge. Generally I have found that with GOEX a compression of between .250 to .400 generally works best with just about every rifle being a bit different. Then I have to redue the test when I change powder lots.

[montana_charlie]

It should work in place of the bullet seating plug in the seating die.
I believe the compression plug is meant to be used in the expander die...not the bullet seater. Unless you shoot 'fireformed' cases (that don't need expanding) it's more convenient to have an extra die body...rather than be switching the expander and compression plugs in and out.
CM

[Southern Son]

+1 on what CM says. I got lucky and a friend who is a gunsmith gave a compression plug in a die. He made the plug out of a bit of threaded rod and the die body from an old Ruger heavy barrell he had taken off a rifle when he re-barrelled the rifle for a fellow. If you choose to use the compression plug in you expander die, then you will have to find your previous settings every time you change back and forth between the expander and the compression plug.

[Muddy Creek Sam]

Does an M Die Have to be caliber specific, Or can I just turn an adapter to put the Compression plug in the press? Does it need to have the outside to stabilize the brass?

Thanks,

Sam :-D

[John Boy]

Yes Sam ... caliber specific ... http://www.buffaloarms.com/browse.cfm/2,150.html

[runnin lead]

My first compression die consisted of a body good up to .50 cal& a stem or plug that was ordered seperatly& cal specific,it sucked ! for 45-70 ,no centering or support, mashed a lot of brass.
The ones that I am using now were made of old 7mm mag & 300 wbymag dies.
someone I know heated the ends of the dies up w/ oxy accetelene torch & machined a lead in chamfer in the end and made a plug that threaded on the decapping /expansion stem,I think he may have had to cut new threads on the stem .
They work great, no more mashed brass

I think you can order an extra appropreate die body for the compression stem that you bought from buffalo arms

[runnin lead]

To set the compression die the method that I use is to first make up a dummy with the bullet just touching the lands,then determine how much powder it takes to reach the base of the bullet after drop tubing, I then place in a wad and seat a cull to the depth of the dummy,I then remove the seating die run the press up , grab the bullet with a pair of pliars and pull down on the brass pulling the bullet,I then run the brass back up & adjust the die body & stem so the plug is just touching the wad.
The ammount of powder that I used is also my starting load, work up from there
The amount of my starting compression is the thickness of my wad

[Don McDowell]

If you are loading 45-70 with 500-540 gr bullets and seating to the driving band or there abouts, the Lyman "M" die as is is just right for compressing powder and wad, and just flaring the case mouth enough to seat a bullet without shaving the corners of the base.:drinks:
Same deal in the 40-65 and 400 gr bullets.:-D

The compression stem is meant to replace the expander in the lyman and rcbs dies.