Tumbling Powerbelts?

[Ky Bob]

What would cause bullets to tumble when they leave the barrel? I shot a few rounds of Powerbelt 275 and 295 grain with two pellets 50gr of Pyrodex? I look at the target and one could see they were tumbling at 50 yards

Rifle is a CVA Accura .50 with 1:28 twist

[mykeal]

Tumbling is caused by the projectile losing stability, which is imparted by the rifling in the bore. Loss of stability can be due to many different things: shallow rifling and a loose fitting projectile, a loose sabot/bullet connection, low muzzle velocity/energy, etc.

Your numbers are good (275 gr bullet, 100 gr powder, 1:28 twist). I'm going to suggest your Pyrodex pellets are being crushed and not fully burning, resulting in low muzzle velocity/energy. Or perhaps they are degraded by humidity (Hodgdon says Pyrodex is adversely affected by humidity) during storage. They can also be easily contaminated by the oils in your fingers or residues from swabbing/cleaning the bore.

Honestly, I have little respect for Pyrodex or 777 pellets. I believe they are inconsistent at the very best, and next to worthless at the worst.

Switch to new Pyrodex RS loose powder, or better yet, loose real black powder and see if that helps. And I'd back down to 80 grains for your 50 yard shots, although that has nothing to do with stability, just accuracy.

[Ky Bob]

Thanks,Mckeal. I have some loose Blackhorn powder that I will try. I saw an advertisement a few times about some new pellets made by IMR and called White Hots. I have been seating the bullet pretty hard so your right on maybe I'm crushing the pellets.

[Mark whiz]

I would also suggest that before loading a powerbelt - slip the cup off and on the post a few times and put a little lube of some sort on the post before putting the cup on the last time.........................if that cup doesn't come off quickly, it will really mess up the flight of the bullet.

You can also drop your powder charge down some too - powerbelts are like women.................they do NOT like to be pushed too hard.

[W. C. Quantrill]

Try Black Powder, like Goex FFg. That is why they call them Black Powder rifles.

[Pahoo]

Try Loose Triple-7, FFg. or FFFg and put a bore button between the powder and PowerBelt. That is why they call them In-Line rifles.



Be Safe !!!

[2amencw]

A great way to improve accuracy with powerbelts is to throw them inn the garbage and use a better bullet. Try something like dead center or shockwave. Higher velocity usually gives less accuracy. I cant stand powerbelts. I have alsway been suspect of a designs that suggests firing a squib load to help the bullet grip the rifling better.... what??? carbon and fouling will somehow resist the hardness of the jacket and cause the rifling to spin the bullet...not likely. I see something a little more akin to a Brown bess try to hit the broad side of a barn. Avoid the power belts and find something that takes some effort to load. You will see accuracy go way up. CW

[FrontierGander]

Powerbelts are fine. You just need to start playing around with some loose powder and primers. I'd suggest either some Pyrodex RS or 2f Triple 7 with winchester 777 primers or Winchester W209 primers. Start at 80grs and work your way up until accuracy falls off.

I'd suggest the Platinums too, they load a lot easier than the regular copper coated powerbelts.

And whatever you do, do Not use a bore button!! I tried it once and the bullets shot horrible. The plastic gas seal is what does the job at holding the bullet in the bore and sealing off gasses.

[Ky Bob]

I shot some Barnes Expander 250gr bullets today with 100grs of Blackhorn 209.
They left prefect holes although I did not spend enough time getting them to group like I would like.