[Steve V]

Hi Marshall, I shoot 41 mag (a 6 1/2" Blackhawk and a 7 1/2" Bisley). On checking the cylinder throats they appear to measure about .408 with a caliper. I tried several brands of lead bullets and they all measured between .410-.412, depending on the brand. It is very, very hard to push even the smaller ones thru the cylinder throats. Any thoughts on this? What size bullet would you recommend, I'm assuming your .410, but I'd like your opinion.

Thanks, God Bless,
Steve V

 

[Marshall Stanton]

Steve,

Slug those throats to make sure of the acutal diameter.   Using calipers will put you in the ballpark, but are a poor definitive answer to determining actual, precise cylinder throat diameters.

Finally, if they are really that tight, I would highly recommend opening them up,( or having it done) to a .4105".   This diameter will allow excellent accuracy with .410" diameter bullets, yet still allow for a slight buildup of carbon and powder residue in the throats and still have ammo chamber easily.

If the throats are under .4095", your accuracy with cast bullets will never be what their potential could be with larger throat dimensions.   They will act like an undersize sizing die, giving you an undersize bullet to traverse your bore.

Only slugging will tell for sure, so give us a report once that is accomplished!

Slugging instructions are found on our FAQ

<a href="www.beartoothbullets.com/faq/index.htm" target='_blank'>www.beartoothbullets.com/faq/index.htm</a>

keep us posted, and God Bless,

Marshall

 

[Steve V]

Marshall, you were right, slugging the cylinder proved that my caliper readings were low. By slugging, the throats measure between .410 and .4104. Would you recommend the .410 bullet?

Thanks, God Bless,
Steve V

 

[Marshall Stanton]

Steve,

That's great!  Yes, a .410" bullet will shoot very well in your gun... probably better if the constriction in the bore where the barrel shank screws into the frame is eliminated with fire-lapping.

.410" diameter and your gun were made for each other!

Good news, and God Bless,

Marshall