Search found 1647 matches

by mtngun
Wed Jan 31, 2018 9:24 am
Forum: revolvers
Topic: S & W N-frame Project
Replies: 107
Views: 30382

Re: S & W N-frame Project

I recut the boat tail cavity to a bevel base. https://imgur.com/akzfKgb.jpg The bevel base version of the "silhouette" bullet was not as inaccurate as the boat tail, but it was still inaccurate. A switchy 5 - 10 mph wind did not help, nonetheless there was no hint that the bullet wanted to shoot sma...
by mtngun
Tue Jan 30, 2018 6:19 am
Forum: design & sizing
Topic: Crimp grooves
Replies: 1
Views: 1703

Re: Crimp grooves

No. Most double crimp grooves are too small.
by mtngun
Mon Jan 29, 2018 11:24 am
Forum: revolvers
Topic: S & W N-frame Project
Replies: 107
Views: 30382

Re: S & W N-frame Project

The Aerodynamics of Revolver Bullets Ross Seyfreid once wrote that the BC of revolver bullets is zero. That's only a slight exaggeration. Even the more streamlined "silhouette" type revolver bullets still have a sucky BC. Combine that with low velocity and you get a lot of wind drift. Here's the dr...
by mtngun
Mon Jan 29, 2018 11:05 am
Forum: revolvers
Topic: S & W N-frame Project
Replies: 107
Views: 30382

Re: S & W N-frame Project

Here's a goofy bullet design. The nose is similar to the various designs made for IHMSA silhouette, but the base has an 8 degree boat tail. While the boat tail might improve the BC a tiny bit, that's not why I did it. I did it because an 8 degree boat tail is reputed to improve stability in the tran...
by mtngun
Mon Jan 29, 2018 6:21 am
Forum: revolvers
Topic: S & W N-frame Project
Replies: 107
Views: 30382

Re: S & W N-frame Project

Go right ahead, Lee.
by mtngun
Thu Jan 25, 2018 11:51 am
Forum: revolvers
Topic: S & W N-frame Project
Replies: 107
Views: 30382

Re: S & W N-frame Project

I should mention that the cavity for the 180 gr. BB control bullet was originally cut to drop out right at 0.358" with reclaimed shot, with the expectation that PC coating would increase the diameter. Now that I am doing some uncoated experiments with other alloys I needed the bullets to drop out a ...
by mtngun
Tue Jan 23, 2018 6:32 pm
Forum: revolvers
Topic: S & W N-frame Project
Replies: 107
Views: 30382

Re: S & W N-frame Project

Some trial and error revealed that air-cooled reclaimed shot bullets would be dinged by a 6-jaw chuck, but water quenched bullets would not be dinged (a 5C collet might work better but I did not have the appropriate collet on hand). So I heat treated the bullets prior to cutting the hollow point. I ...
by mtngun
Mon Jan 22, 2018 7:47 pm
Forum: revolvers
Topic: S & W N-frame Project
Replies: 107
Views: 30382

Re: S & W N-frame Project

While re-reading David Bradshaw's experiments with the "volcano'd" WFN's, I stumbled across this tidbit about the Taylor throat in one of David's pet Ruger 45LC's. Its 0.800" long Taylor freebore strikes me as longer than ideal, however it may have been cut that long to clean up the barrel constrict...
by mtngun
Mon Jan 22, 2018 7:21 pm
Forum: revolvers
Topic: S & W N-frame Project
Replies: 107
Views: 30382

Re: S & W N-frame Project

I have been thinking about why the bullets with the .357" band added to the tip of the ogive did not shoot well. :geek: There are two challenges that any bullet has to overcome. First it must fly straight while passing through the gun. Second, it must fly straight while passing through the air. If i...
by mtngun
Sat Jan 20, 2018 7:17 pm
Forum: revolvers
Topic: S & W N-frame Project
Replies: 107
Views: 30382

Re: S & W N-frame Project

Since the "smooth" version of the control load had shot surprisingly well on January 13, I decided to try a couple more versions of the control load. https://imgur.com/uhPhhbd.jpg The uncoated version of the 180 gr. BB did "OK." If you disregard the one wild flier, the average group drops to 3.53", ...