How much is too much Leade. ?

Discussion of BPCR loading techniques, SAFETY, Case Cleaning and Prep, Indexing, BP Choice, Primers, Wads, Compression, Drop Tubes, Vibration, Load Testing, etc.
Singleshot S.A.
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How much is too much Leade. ?

Post by Singleshot S.A. » Wed Oct 30, 2019 3:47 am

Hi all,
I own a Husky Rolling Block with Douglas barrel in 40/65. It shoots well with a Breech seated Steve Brooks 2 diameter bullet of 400 grains.
I seat the bullet to engrave the second to last band. Reason for this is the breech was cut with over 200 thou of leade or free bore and I have always been concerned about that gap if I seated the bullet in to the Base band. These locally built rifles are about 15 years old and no problems.
Now I have recently sold another 40/65 Douglas which was pretty much a standard breech, and I have two bullet molds that shot exceptionally well in that rifle, but they are traditional Base band molds. Sooo.........
How much is too much gap. ???
Should I use a felt wad to fill part of that gap or do I need to fill the whole gap. ??

Brent
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Re: How much is too much Leade. ?

Post by Brent » Wed Oct 30, 2019 5:56 am

I would seat the bullet until it starts engraving, which it sounds like you are doing with good results. So, I'm not sure what you mean by gap that you would fill with a felt wad? A gap between powder and bullet? I would fill that with a wad, or more likely, more powder (black).

If you have something that works well, why change it?

I guess I am not understanding something.
I'm not from here, I just live here.

Singleshot S.A.
PostsCOLON 90
JoinedCOLON Sun Aug 30, 2015 6:19 pm
LocationCOLON Adelaide. Sth Oz.

Re: How much is too much Leade. ?

Post by Singleshot S.A. » Wed Oct 30, 2019 3:46 pm

Hi Brent,
There is quite a gap behind the Breech seated bullet even by seating to the second band. If I try the other bullets and seat to their Base band there will be even more gap. Nearly .200 " 3/16th inch. Is it too much. I am using a full case of drop tubed 1 P Wano with a .030 poly wad. Some shooters talk of filling that gap in front of the case with a felt or cork wad.

TexasMac
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Re: How much is too much Leade. ?

Post by TexasMac » Fri Nov 01, 2019 2:16 pm

So what are the negatives if any of a long freebore when seating the bullet back in the case & having to jump the freebore? I'd like to hear from shooters that have direct experience, not guesses or assumptions. A shooting friend recently acquired a Pedersoli .45-70 Sharps with a lot of freebore. Although a chamber cast has not been made, a visual estimate it it's about 0.250". He shot ammo that was loaded for a Browning .45-70 BPCR which does not have any freebore & did OK but not great at a recent match. I have a lot of experience with a Browning .40-65 BPCR which has a about 0.190" of freebore but I've always loaded with the bullet in contact with the leade or no more than 0.005" off the leade & have not experimented with seating the bullet deeper. The only negative that I can think of when "jumping" a long freebore, assuming the freebore diameter is the same as the groove diameter, is the bullet may not bump up as quickly as when the bullet is in contact with the leade and the chances increase for blowby & gas cutting.

So does anyone have direct experience with jumping the freebore & experimented with various seating depths?

Wayne
NRA Life (President's Council) Member, TSRA Life Member, NSSF Member
Click on http://www.texas-mac.com/index.html to my home page containing information on my Browning/Winchester BPCR book & associated articles.

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