Paper patch cartridge

[RobP1]

I just loaded and shot my first paper patch bullets. Can someone explain what I have going on here. The cartridge has what seems to be a hard baked on black ring around the lip of the cartridge after firing. Am I have a gas leak problem here? thanks

[Mr.doug]

Moisture in the chamber after wiping will do that. Or the case was not annealed and is not
Blowing out enough to seal chamber. If it’s moisture, use a chamber mop after wiping.

[RobP1]

that could be the problem. I use a bore wiper with 2 felts and it is pretty saturated. even though I run a dry patch behind it. I do anneal all my cases. I only use a .030 veg wad on top of the powder. I'm thinking of adding a wool wad also.

[Mr.doug]

If that’s a 45-70 you are shooting I would not go more than an .060 wad or you will giving up
To much case capacity for powder.

[RobP1]

its a 40-65

[Mr.doug]

I have a browning 40-65 I just shot 56 rounds out of Saturday and had some
On my casings with the same look to them. I chose not to chamber mop
At this gong match. Acuracy was very good for me so don’t think it matters but
It takes a while in the tumbler to get rid of the discoloration. BTW I use
An 060 vegi. Wad with Swiss 1.5 and get 67 grains in the case with .130
Compression

[RobP1]

Thanks for the recipe. I've been working up some loads, trying to find the sweet spot. last 40 rounds was with 63 gr. I'll try 65 and then 67.I'm finding the more I increase the better the performance. I started at 59 gr. I'm also using Swiss 1.5

[Mr.doug]

The main reason I can get 67 grains in that case is a 3’ drop tube
A long freeboar and first driving band reduced. 3 grease grooves are exposed when bullet
Is seated.

[RobP1]

I'm paper patching to bore dia. Hand seating bullets. I drop tube also

[dirtball]

Are you using a straight sided bullet or Dual Diameter PP Bullet? If you are using a straight sided bullet are you crimping the case to hold the bullet? If so, that crimped portion is not blowing out to seal against the chamber wall and that is the portion that would be getting the blow back.
Dave

[RobP1]

I use a slight taper crimp. That may be my problem. thanks for pointing that out. This is my first year with paper patch bullets. So I'm learning as I go. So you're suggesting not to crimp and just hand seat the bulletin into a snug slip fit? yes this is a straight sided bullet

[dirtball]

As long as you are shooting straight sided PP bullets in a chamber cut for Grease Groove bullets you are going to have to continue to taper crimp to hold the bullet in place. The carbon blow back is something you have to live with. BUT don’t forget to anneal often or the necks will start to split from being worked. What I did was to go to a dual diameter PP bullet, now I shoot, clean and reload. No sizing, no crimping but I still anneal after 5 or 6 firings. Finding the right mold is the trick, you need to consider your chamber neck diameter, the wall thickness of your case, and then allow 6 to 8 thousandths for paper. I ended up with https://www.buffaloarms.com/405-390-grain-paper-patch-1-jim405390e.html It works in both my Browning 40-65 and my Shiloh 40-82, but with different paper. Buffalo Arms has several 40 cal DDPP molds to choose from depending on your chamber dimensions brass thickness and twist rate.
GOOD LUCK
Have FUN!!


Dave

[RobP1]

.405? You must be patching to groove dia.? Or do you not wrap the .405 base? I'm not familiar with duel diameter. It appears the base is patched to groove dia. and the rest is bore dia. Correct? What is the advantage?

[dirtball]

That is the advantage of a DDPP bullet; no sizing, no crimping and near perfect bullet alignment in the barrel. The base on this bullet is .19” long is patched to .410 and is a snug fit in case. I seat it .12” into the mouth of the case. The rest of the bearing surface of the bullet patches to just a little over .400 and is a snug fit to the bore diameter of the barrel.
There is a wealth of information on this and other sites. Just use the “Search” feature.

Dave

[BLAHUT]

In my 45/70 I do not size cases; I do not crimp; indexed; they are single loaded so no need; the bullet ( greaser ) is just sitting in the case; you can slide any one of them out without any pressure; when chambered, they engage the rifling, just touching; one over powder card wad, one plastic cut wad; took a while to fine what the gun liked; now very accurate out to 1000yds...

[RobP1]

I spent the day at the rifle club yesterday. I cast and loaded three different PP bullets. One is patched to grove dia. the next one patched to bore dia. and the last one patched duel dia. I shot 25 rounds of each the straight sided patched to bore and 25 rounds of the duel dia. I only shot about 10 rounds of the patched to groove as I'm thinking of using that round with smokeless only. All rounds were loaded with 65gr of Swiss 1.5 with a .030 veg wad and a dry wool wad with .100 compression. The wool wad seemed to have solved the blow back problem I was having earlier. When all was said and done I would have to give the advantage to the duel diameter bullet. Hitting the rams 9 out 0f 10. Of course this is from a bench rest with Shaver mid range sights. The straight sided bullet performed well averaging 7 out 10 on the rams.I'll test more with both rounds but after 75 rounds the weak link is the nut behind the butt. It was a nice calm day for the test.