It this what you’re talking about?

Tom Klinger

SAMMI and most other reamers do not have the cylinder section. You need to have it cut that way when you order a reamer.
Dan T designed it into all of his match caliber reamers. I use it on all the reamers I order…


Tom Klinger

If you resize, neck size only.Then use a straight expander die. It will make the case neck straight to match the conical cut chamber.
With this style chamber reamer, you shouldn’t need to resize after firing. Finger seat the bullet and maybe slightly flair the neck for easier bullet seating. Then remove the flair.


Tom Klinger

frnkeore wrote on Jan 2^nd, 2026 at 5:19pm:


I agree Frank. I think one and a half degrees is better than three. I had my bpcr reamers ground with one and a half degrees and they shot very well. I had several conversations with Dave Manson at Manson reamers and he said Theodore talked to him quite a bit about what he thought they should be and I think he took a lot of advice from Dave. Dave told me that 3° for the 45-70 is better if you're going to shoot both cast bullets and jacketed bullets.

I think it's got more to do with the shooter and his spotter than the leade angle in bpcr. A lot of the Lodi guys shoot nothing more than the standard chamber that Shiloh has in their rifles. I know that Mark Schuenke and Cliff Gregg have become a formidable pair and they have done well at the winter matches in Phoenix. I've shot next to them several times and it was amazing to listen to them and the wind calls that they gave each other but yet each one seemed to keep him the shooter in the center of the paper. I would guess Steve Fehringer has nothing special going on with his barrel either.  I wonder if Dave Gullo even knows what leade angle is in his rifles.

Bulseyetom wrote on Jan 1^st, 2026 at 8:29pm:


This has been a subject I’ve always been interested in since writing the book on the Browning BPCRs.  For their .45-70 chamber, being SAAMI members, they used the SAAMI chamber specs which uniformly tapers from just in front of the rim recess to the chamber mouth, followed by a 12-degree 45-minute transition step to the bore with no leade.  Their .45-90 (no SAAMI spec) has essentially the same chamber but, of course, a bit longer, followed by freebore (extended throat) and a 1.5-degree leade.  Therefore, for both chambers, the chamber taper essentially matches the case wall taper.  So, even after fireforming, the inside diameter of the case neck is uniform resulting in the same tension throughout the length of a straight-diameter bullet.  But that’s not the same with their .40-65 Win chamber.

Since the .40-65 Win. is not specified by SAAMI, Browning designed the chamber with a cylindrical (constant diameter) neck followed by freebore & a 1.5-degree lead.  Due to the cylindrical chamber neck, to get uniform neck tension, the case should 1st be fireformed, then the neck outside turned or, better yet, inside reamed with a chucking reamer to a uniform case wall thickness.  Since this is similar to the Dan Theodore chamber design with cylindrical neck, the same case preparation should be used for the DanTDesigns chambers.

Wayne