Blackhawk 44 Mag bore size ?

[Hylander]

What is the bore suppose to spec at?
I want to order pin gauges to check for barrel constriction.
Thanks

 

[Enigma]

IIRC, nominal SAAMI spec for .44 Mag handguns is .429"; rifles is .432". That's GROOVE diameter, BTW. It's much less expensive to slug the bore and stop just short of the receiver threads. Drive the slug back out the muzzle and measure it, then run another slug all the way through and compare them.

 

[contender]

Buying individual pin gauges can get expensive. A good full set is cheaper in the long run.

But Enigma is correct. You can get the groove diameter,, easily,, and it'll be in the neighborhood of .428-.431 usually. (.429 is considered the correct size.) But that will NOT be the sizes you need for using pin gauges because they will be riding on the lands,, not the grooves.

 

[Hylander]

Thanks,
I'm looking for what the bore diameter should be and then I can buy pins that very small to larger. I am in the market to buy and pretty sure the seller is not going to let me slug the barrel, but pretty sure a seller would let me check with gauges.

 

[Cholo]

The bottom line? I've never given it a second thought, neither should you.

No sense overthinking this barrel constriction thing. If it shoots wildly, then deal with it.

 

[jgt]

Different barrels have different groove depths. Let say you have a groove depth of .004 and everything is uniform with no tight spots. In a .429 barrel you could have a .421 gage pass through the barrel. You need to be careful how you use these gauges though, because if they are like mine, they are steel and have sharp edges. If you get to a tight spot in the barrel, it is time to take that gauge back out and try the next smaller size until you get one that passes through freely. You could cause all kind of trouble if you stick a gauge in a barrel. That is why people choose to drive a lead pig through the bore and measure it noting any tight spots in the process. Mainly they use the bore gauges to check the cylinder throat diameters for size and uniformity.

 

[s4s4u]

A pin gauge will only indicate the distance from land to land, the high spots. That isn't going to tell much of anything. Slugging the barrel, you can feel a restriction as the bullet, or egg sinker, passes through.