BH 209 powder

[captaindad3]

I loved Black Mag II (and III). My supply is dwindling. Getting ready to try another propellant. Any opinions on BH 209 powder?



I am shooting a Gonic Arms GA87 Magnum. This rifle is MOA out to 200 yards with Black Mag II. Only use this rifle elk hunting.

The barrel is made from #4140 chrome moly steel that allows for chamber pressures in the range of 30,000 PSI. It has a 1-24” twist and button rifling .005 deep. The front portion of the barrel is recessed with a free bore of .700. By incorporating a 17 degree taper in front of the bore the conical is started perpendicular to the bore. Bullet canting one of several obstacles a shooter must overcome during loading to attain accuracy with a conical is eliminated.

[GMB54-120]

Isn't the Gonic a "slam fire"? If so using BH209 is NOT recommended.

[captaindad3]

I believe it is a "slam fire". It is a closed breech rifle, but in its present configuration, does not exert pressure against the primer rim to hold it in the adapter. I would work up slowly in load, looking for backward primer migration.

What is my best powder option, if not BH 209?

[GMB54-120]

You could try Alliant BlackMZ but i didn't care for it at all. Some of the newer reviews though have been far more positive than when i tried it.

I would look for some Swiss or Goex has the new Old Enysford for much less than Swiss. Im not a fan of most subs other than BH209.

[captaindad3]

Is the problem with the BH 209 in "slam fire" guns that it sets the primers back because they aren't held in by a breech bolt leading to blow back? Does this blow back lead to misfires due to part of the flame not going forward into the charge? My Gonic has the closed breech modification which would eliminate flying pieces of primer. It does not, however, support the outside edge of the primer to hold the primer in the nipple. Is BH 209 higher pressure than other BP substitutes or a different pressure curve? Anyone have links to a discussion on this to educate me? Thank you!

[10ga]

I posted a partial reply on your other thread. You need to build pressure and heat to ignite BH209. Even if you could get ignition the BH209 pressure curve and top would give you a very high level of leakage/blow back, probably enough to give gas cutting of plug and bolt face etc... a dangerous situation.

I would recommend you go to real "holy black". I used Swiss for competition and hunting and most anything else for otherwise. The Gonic was designed for real black powder and shoots real good with it. I suggest you stick with what it was designed for. Other than that I'm thinking you could use the 777 or Pyrodex but I prefer the real stuff. 10