Out of retirement...

[Micah]

I was thinking about shooting my CVA Hawken, that I built from a kit, this weekend. It's got a .54 cal. barrel, made in Spain, with the infamous "700kp/cm2" proof mark. While it seemed fine with my conservative loads 12 years ago when I built it, I'm a little concerned about losing my hand or part of my face. I cleaned it very well back then, and I live in NM, so it's not rusty, but what about residual corrosives in the ("non-removable") breech plug threads and what not? Can I remove the breech plug? Or should I just junk the thing? Your input is greatly appreciated.

 

[bwhoffman]

how about a real good cleaning,use a breech face scraper if in doubt, and run some white patches down on a bruck and see what they look like.
personally, I would clean well, try a non max load,say 50 grains, and fire it remotely a time or two. this will keep the gun away from your face.

Brett

 

[Rebel]

If there is no rust in the barrel it should be fine. As long as it was cleaned and oiled well before you stored it there should be no problem shooting normal loads in it.

 

[Zonie]

I have always suspected the "700kp/cm2" problem came from someone with a "magnum" mindframe who loaded his/her gun with mega-loads (150 grains?) of powder behind heavy slugs.
It also may have been caused by someone who loaded some kind of "black" smokeless powder into their gun and didn't want to admit their stupidity. That will do it every time.

If your gun shows no sign of rust it should be OK to shoot with reasonable powder loads and a patched roundball like it was designed for.

zonie

 

[Runner]

Send it to me. My match gun is a CVA Hawken most of the time. I will not admit to all I have done with that gun, but I will say this. It is down for stock replacement because the factory stock split under the recoil when I was testing 777 a couple of years back under middle weight conicals. I used bedding compound to cure the cracks and kept shooting it until recently. It is well broken in now, maybe. It has been accurate and dependable for many years. The load that killed the stock was way too much 3f 777 under a 385. The forestock spread and cracked full length under the recoil when the wedge pulled. Me, I am not worried about CVA barrels at all!

 

[omgb]

I wouldn't worry about it. Use a RB and up to 100 grains without even batting an eye. Conicals and heavy charges of 3F or even 4F are another thing. My guess is though that 80 grains of 2F and a nice snug RB are going to shoot well and of course, will be more than safe.

 

[Zonie]

For what it's worth:

700Kg/cm2 is equal to roughly 9940 PSI.

The Lyman "Black Powder Handbook" 2nd Ed gives these pressures for a .54 cal cal 28 inch long, 1:48 twist barrel.

Goex FFg powder under a .535 dia patched roundball:
60 gr = 5,100 psi
70 gr = 6,300 psi
80 gr = 7,500 psi
90 gr = 7,900 psi

Goex FFFg powder under a .535 dia patched roundball:
40 gr = 8,500 psi
50 gr = 9,300 psi

Pyrodex RS powder under a .535 dia patched roundball:
50 gr = 5,100 psi
60 gr = 6,100 psi
70 gr = 7,100 psi
80 gr = 8,200 psi
90 gr = 8,700 psi
100 gr = 9,200 psi

Pyrodex P powder under a .535 dia patched roundball:
40 gr = 7,200 psi
50 gr = 8,000 psi
60 gr = 8,900 psi

Pyrodex RS under a 430 gr T/C Maxi
60 gr = 11,700 psi

As you can see, if your shooting a patched roundball, there are a number of loads you can use without exceeding the pressure the gun will withstand.
Using FFg powder or Pyrodex RS gives pressures which are well within the hunting load area.
Using the faster burning pistol powders, either FFFg or Pyrodex P can create some potential problems and as shown with the Maxi it is easy to get into pressures that could be unsafe.

zonie

 

[Jim-Iowa]

Based on a recent experience with my old CVA Barrel. Don't even try to pull the breech plug!
All you'll manage to do is bugger things up and it will still be tight. I tried it and when could not budge it, thought I was doing something wrong.
So took it over to Bookie's and he could not get it out either. His advice was to cut it out and fit a new plug. I did file off all the burrs and put it back together as is. There was a discouraging amount of surface rust in the bore. A lot of cleaning including JB polishing paste on a patch wrapped around a bronse brush got it cleaned up much better than I expected only a couple very small pits in the bore. It is useable as is.
Another trick I learned from Bookie was a cheap bore light for inspection. Go to the sporting goods dept of your favorite Big Box Store and get one of the replacement lights for a lighted bobber. Drop it down the barrel and it lights things up big time.

 

[Micah]

Excellent! I'm gonna go for it, and I'll post my results here. Thank you all for your input, you are all invaluble. -Micah.

 

[omgb]

I cleaned up the bore on a very tired Lyman GP this way: First, I cast up some TC maxiball slugs using wheel weights. It has to be wheel weights to work. Then I rolled 30 of them in LBT bore lap paste ujntil they were well loaded with lap compound. Then I cleaned the bore of any grease and all fouling. I shot one of the slugs over 35 grains of 4F. I cleaned, dried the bore and did the same thing until I had fired all 30 of the lapping rounds. This left me with a very clean and smooth bore with nice crisp rifling. The rust was gone as were almost all of the pits. Only one or two of the worst remained. What I got out of it were 5 touching shots at 50 yards and easy loading for each shot. It saved an otherwise poor barrel and turned a weak shooter into a tack driver. The 4f bumps the slug up quickly and is just stout enough to get the slug out of the gun without leading.

 

[rich e]

" I shot one of the slugs over 35 grains of 4F. I cleaned, dried the bore and did the same thing until I had fired all 30 of "

Everything I ever read or was told, was never use 4ffff for a main charge, only to prime, are you sure your being safe. :hmm:

 

[Runner]

Make up a slug as suggested. Start it into the bore and ram it down. Start a ball puller jag with the slug in the bore and use it to pull the slug up and down the bore to lap it clean. When it starts to get easy to move, turn the ball puller screw into the slug another turn. That will force it out against the rifling again.

 

[paulvallandigham]

I have to agree with Rich e, about the danger you are in using 4 Fg in the barrel. My God, the pressure of that 35 grains is tremendous. It is only a testament to the strong construction of that gun and barrel by the manufacturer that you are able to use your hands to tell us about it! NEVER USE FFFFg POWDER IN THE BARREL FOR ANYTHING! If you insist on shooting a barrel smooth as you describe, use only 3Fg powder to do so. It is fast enough, and won't endanger you, the gun, or anyone standing around you when you fire the gun. The better method is the mechanical one described By Runner. You can use either a Round Ball, or a conical. He is also correct that by turning the ball jag a 1/4 turn, it will drive the lead further into the grooves if it seems to be getting easy to move in the barrel after a few strokes.

Another way of doing this is to use a good Stainless Steel range rod, drill a hole through a ball or bullet, then run a 10/32 machine screw with a small washer in front of the head through the ball and into the rod. Either put a cleaning patch with the honing compound impregnated in the cloth down the barrel in front of the ball, so that it wraps around the ball as would happen when loadd normally, or coat the ball or bullet liberally as you are currently doing with the compound, and then drive the ball into the barrel as it looses up with work, you can turn that machine screw a little to espand the ball or bullet a little and tighten it up for more passes with the compound. Obvously, use soft lead only, and not any alloy bullet.