Leading????

[tomme boy]

Ok, I have a 45 colt single shot NEF. I am getting leading in the first 2" of the bore. I am using several differant bullets. I am sizing them at 0.454" an using NRA lube. The the troat measures 0.4525" same on the other end.

I am using WW's and range lead that are water dropped. It is worse with the RCBS RNFP 255 gr. than the other ones. I have tried air cooling and staight WW's an straight range lead. I have used Red Dot, Blue Dot, 231, Uniuqe, Longshot, H110, IMR4227. They all do it to some degree. The faster powders seem worse.

I am thinking that the boolits are stripping as they enter the rifling. I do not see anything wrong with the throat as to defects. This only see's cast. It is not that bad. It cleans up with about 10 stroaks with a brush with some choar boy wrapped around it.

Does anyone have any ideas?

[40Super]

Did you run a slug down the entire bore? Some barrels have tight areas(like where threaded and attached to frame)that will swage the bullet down,and then gas cutting will occure as soon as the bore "opens" back up.

Another would be wheel timing? The cylinders don't line up with the bore and when fired,as you said, it cuts one side of the bullet. Does the leading occure on the exact same side of the barrel?

Edit: I was thinking revolver,my bad

[geargnasher]

I have one of those but never had leading problems at all, only accuracy problems from the stupid huge throat. I had the best luck with grease-groove boolits using the Lee 457-340-RF sized to .454", seated to engrave, and loaded over a case full of Reloader 7. I've used every single one of those powders except H110 and almost a dozen different boolit styles, the problem was always getting a boolit that was long (heavy) enough to reach the rifling to engrave slightly AND fill the throat. The throat on mine will accept a .457" boolit easily for about .300" forward of the case if I remember right.

I ended up paper-patching for mine, works like a champ that way, using fireformed brass and softer boolits patched to the throat (patched boolits sized .457", cores .447-ish).

As far as the leading goes, I think the issue is gas cutting the boolit before it gets engraved well and sealed in the barrel, i.e. powder gas is blowing around it while it transitions the throat. I'd try a compacting filler like BPI Original shot buffer (available at Midway etc.) on top of a starting charge of 2400 or Blue Dot to help seal behind the boolit as it makes "the leap" to the rifling through the oversized throat.

Also, make sure the throat-bore transition doesn't have a sharp ledge on it, it should be a smooth taper from the end of the chamber to the rifling.

Gear

[geargnasher]

Did you run a slug down the entire bore? Some barrels have tight areas(like where threaded and attached to frame)that will swage the bullet down,and then gas cutting will occure as soon as the bore "opens" back up.

Another would be wheel timing? The cylinders don't line up with the bore and when fired,as you said, it cuts one side of the bullet. Does the leading occure on the exact same side of the barrel?

It's a break-action rifle, dude!

Gear

[tomme boy]

Do you think that seating this one out farther with no crimp would work. I just figured that it is supposed to have a crimp. Everything I heard about the Colt was to have a heavey crimp.

http://www.accuratemolds.com/bullet_detail.php?bullet=45-300F-D.png

This one shoots good.

I have pushed a slug down the length. I could not feel any tight spots. I am wondering about a softer lead to seal faster?

[geargnasher]

No way if your throat is anything like the one on mine. The nose on that boolit is .436" which is about .012" smaller than bore diameter and around .017" under groove, it won't pilot or seal until the front band is fully engraved, by which time it will leak gas and get a crooked start.

No need to crimp at all with a single-shot as long as you remove just enough of the bellmouth so it will chamber. Even leaving some bellmouth is fine. Looks silly, but it actually helps center the cartridge in the chamber. The heavy crimp in a groove that you read about is to keep the boolits from pulling under recoil in a revolver. Unless you're loading "dual purpose" ammo to be shot in both your NEF and a revolver, you won't need to crimp at all.

Here's what I'd look for:
http://www.accuratemolds.com/bullet_detail.php?bullet=45-325D-D.png
Note the long, band-diameter section above the crimp grooves, long nose, and gentle taper with no step at the front band? That's what you want. You can seat it to just contact the lands then you close the action and fill all the grooves including the crimp grooves with lube, no need to get a boolit that exactly lines up a crimp groove with the case mouth while touching the lands exactly, just figure out how deep to seat them so the boolit pilots in the rifling.

Gear

[tomme boy]

Well, I just went down an seated a few out to see where the throat is at.

At 1.79" it is firmly into the rifling with the 300gr listed above. I normally seat these at 1.70" Also, there is NO leade. The rifling has a sharp start, no tapor. The crimp was just enough to remove the bell. This seats the boolit so the case mouth is in the center of the middle band of the boolit.

Seated this way, you have to snap it closed. I loaded up 10 this way to try in the morning. I also cleaned the heck out of the bore. It is spotless.

[MtGun44]

Try some without the water dropping.

Bill

[tomme boy]

Well I went to the range today to try out the 300gr ones that I seated out to jam in the rifling.

No go, it is still leading in the first 2 inches. Where it is leading at is on top of the lands. I have a feeling it is happening because of the lack of a leade. I think it is shearing off the lead as it starts.

I shot these with 10 grs of 231. I shot it at 50yds and it actually shot the best group it has ever shot so far. 7 shots went into 3/4" edge to edge. The others went out because of the guy next to me kept throwing hot brass at me an down my back. I know thats what made me throw the 3 shots.

[geargnasher]

I keep a brass catcher for ARs in my range bag, it gets presented when the guy on my left is shooting one, makes things on the firing line much more civil.

I think your leade might just need a polish. Size about a hundred down to about .447 and paper-patch with 9lb onionskin, smear the patch with a bit of JPW and let them fly. Your leade will polish nicely.

Gear

[runfiverun]

i wonder if snapping the action closed is tipping the cartridge up against the roof of the chamber in the front.
try just neck sizing the case.
i know you are shooting a pistol cartridge.
but you are shooting it in a rifle.
you could also shorten the oal by about 2 thou or so, just enough to close with out the fighting the case and putting downward stress on the back of the case.

[tomme boy]

I am neck sizing the case only where the boolit is at. It is only into the rifling about 0.01". You have to snap these actions to make them close. I'm thinking about trying to fire lap it out. I have no way to do the paper patch, but I think a friend has the steel plate and differant grades of lapping compound. I will have to check.

[MtGun44]

Try softer boolits.

Bill