Smokeless Prefit

[Carolina91]

Hey guys i am looking into building a smokeless muzzleloader and am looking at buying a mesa action, mesa stock, and either a hankins or arrowhead prefit. Has anyone done one of these prefit installs? It seems pretty straight forward with the go/nogo modules arrowhead has. Once the headspace is set is there anything tricky to know other than setting the headspace. I appreciate any info given.

 

[LonePeak18]

I built a long range muzzleloader last year. I bought a factory Remington 700 .243 and stripped the barrel and stock. I went with a Hankins 40 cal Prefit. I also bought a barrel nut and the matching wrench from him. I put it in an HS Precision stock. Thing shoots lights out (.5 moa) to 800 yards.

As far as setting headspace goes, I actually made a mistake the first time I did it. I put a piece of scotch tape on the back of a module to give .002" room and put that module into the bolt nose then I closed the bolt and screwed the barrel on until it stopped on the module. This is the way Jeff Hankins suggests doing it. The problem was that I didn't realize that the unfired modules have a little crush or press fit to them the first time you put them into the breach plug. Because of this, my headspace ended up being like .025" too long and my primers would back out that same amount when I'd fire it. I actually shot it like this for the whole first year because it didn't affect the performance but was annoying and probably putting undue stress on my primer pockets. It wouldn't have been a big issue except for the fact that I had my smith install a non-self timing brake. So when I went back and readjusted my headspace, I had to take it back to my smith to get the brake retimed. (So much for trying to save on a non-self timing brake.)

I'm not sure if my experience with the initial crush/press fit of the modules is unique but perhaps a call to Jeff would help clear up questions.

One thing I'll add that I learned when I was shopping for a barrel is that Hankins machines his modules with a taper so that you get a proper seal in the breach plug. Last I checked, the Arrowhead modules do not have a taper. I can't comment on how much of an actual difference this makes, but I do understand the principle of taper fits and their sealing ability. Just something to consider and look into a bit more.

 

[Carolina91]

I built a long range muzzleloader last year. I bought a factory Remington 700 .243 and stripped the barrel and stock. I went with a Hankins 40 cal Prefit. I also bought a barrel nut and the matching wrench from him. I put it in an HS Precision stock. Thing shoots lights out (.5 moa) to 800 yards.

As far as setting headspace goes, I actually made a mistake the first time I did it. I put a piece of scotch tape on the back of a module to give .002" room and put that module into the bolt nose then I closed the bolt and screwed the barrel on until it stopped on the module. This is the way Jeff Hankins suggests doing it. The problem was that I didn't realize that the unfired modules have a little crush or press fit to them the first time you put them into the breach plug. Because of this, my headspace ended up being like .025" too long and my primers would back out that same amount when I'd fire it. I actually shot it like this for the whole first year because it didn't affect the performance but was annoying and probably putting undue stress on my primer pockets. It wouldn't have been a big issue except for the fact that I had my smith install a non-self timing brake. So when I went back and readjusted my headspace, I had to take it back to my smith to get the brake retimed. (So much for trying to save on a non-self timing brake.)

I'm not sure if my experience with the initial crush/press fit of the modules is unique but perhaps a call to Jeff would help clear up questions.

One thing I'll add that I learned when I was shopping for a barrel is that Hankins machines his modules with a taper so that you get a proper seal in the breach plug. Last I checked, the Arrowhead modules do not have a taper. I can't comment on how much of an actual difference this makes, but I do understand the principle of taper fits and their sealing ability. Just something to consider and look into a bit more.

Thanks for the input on this. Good to hear great results!

 

[LonePeak18]

If you want any other thoughts let me know. I only have one year experience but there's definitely a few things I wish I would have known that would have either saved me time or money. I'd be happy to call you to share my little bit of experience if you think it'd be helpful.