Muzzleloader chamber thickness

[biednick]

I want to build a 50 caliber muzzleloader barrel for my Freedom Arms 2008 and am looking for information on the wall thickness at the chamber. I'd be starting with a 416 stainless blank. The picture below shows a cross section of the barrel at the breach. The largest inscribed circle that fits fully in this cross section is .894", which leaves around .197" of wall thickness from a .5" bore. There will be some features milled in the top to accommodate sights, but none of these features will intrude into the .894" circle.

I'm fairly confident this will be fine for non- magnum loads, but I don't have much experience with muzzleloaders and would like to hear input on whether or not the wall thickeness is adequate from those with more experience than me. My other option is converting a 45-70 barrel (which is available from Freedom Arms), but many states require 50 cal or larger for muzzleloading handguns so a 45 would be more limiting.

 

[Rick Richard]

I am not really sure what you're asking, but if it is barrels and specifically Muzzle-loading barrels than I would call Rice barrels in Mocksville, NC with your question. Good luck.

 

[HSmithTX]

You can look at Rice, Colerain, Green Mountain etc and see what bore they will put in what size octagon to get a rough idea of what the wall thickness is. For example, the 58 cal is in a 1" barrel at the smallest, to go to a 62 you have to go with a larger barrel and I think that is 1-1/8". This from memory so please check. Wall thickness .175" gives me the willies thinking about it but it is black powder and pressures are quite low compared to smokeless...... Whatever you do I suggest proofing it when done. It's really not that hard to double charge, double ball/bullet or both, has been and will be done again. Careful measurements before and if it appears unhurt careful measurements after should show how safe or unsafe you can guess it is. Sounds like a cool project to me.

 

[biednick]

You can look at Rice, Colerain, Green Mountain etc and see what bore they will put in what size octagon to get a rough idea of what the wall thickness is. For example, the 58 cal is in a 1" barrel at the smallest, to go to a 62 you have to go with a larger barrel and I think that is 1-1/8". This from memory so please check. Wall thickness .175" gives me the willies thinking about it but it is black powder and pressures are quite low compared to smokeless...... Whatever you do I suggest proofing it when done. It's really not that hard to double charge, double ball/bullet or both, has been and will be done again. Careful measurements before and if it appears unhurt careful measurements after should show how safe or unsafe you can guess it is. Sounds like a cool project to me.

That's how I came to the conclusion that it's probably okay. Rice and Green Mountain both do 7/8" barrels in 50 cal, which leaves .1875". They're .875 across the flats vs. .894 round for what I would end up with.

Proofing is definitely part of the plan.

.175 was a mistake on my part. I was looking at the wrong dimension when I made the post this morning. I'll have .197" at the thinnest spot.

 

[HSmithTX]

10-4, sounds like a plan to me, will be curious to hear what your results are. I am a bit jealous, I don't have anything cooking that is anywhere close to as interesting as this. And you have to video the proofing, I would love to be there for that.

 

[biednick]

10-4, sounds like a plan to me, will be curious to hear what your results are. I am a bit jealous, I don't have anything cooking that is anywhere close to as interesting as this. And you have to video the proofing, I would love to be there for that.

I'll be sure to shoot some videos when I proof it.

I just finished up machining a 22lr barrel for it too. I just need to get down to my dad's to bead blast it and it'll be finished. Based on the initial tests I did a couple weeks ago it should be a great shooter. With CCI SV and a front bag I was shooting 1.5" groups. I think better ammo and a more stable rest should get me sub MOA.

I really like the gun, but Freedom Arms doesn't have a whole lot of caliber choices for it. I've bought 3 barrels from them that cover most of my hunting cases, but need a rimfire and muzzleloader barrel to fill in the gaps.