UN- heat treating?

[XWrench3]

normally, i water drop almost all of my boolits. the "alloy" is usually ww, or ww + 2% tin. i will be "breaking in " a new barrel in the next few weeks (or so i am told by the gunsmith) and i am going to fire lap it right off the git-go. it ids a factory new take off barrel from a custom rifle build. i was reading an article about doing just that, and thier argument was it was best to do it with fairly soft bullets, that way, the tight spots would be "honed" and the looser spots would be left pretty much alone, at least until the bore was the same size all the way down. this made a lot of sense to me. unfortuneately, i have zero straight soft lead laying around. so i was thinking of just de-heat treating some already cast boolits, instead of casting different ones and letting them air cool. do you think these would still be to hard??? or, should i break down and buy some $1.00 a pound + soft lead from eblay?

[XWrench3]

P.S. i do not have a bhn tester. wish i did, but money is VERY limited, andi just can not really afford one. i have been saving for the barrel job for a year. and if it goes over budget, the balance will have to go on a credit card ,augh!!!!

[crabo]

Maybe if you would tell us what caliber, someone might be able to send you a few pure lead.

[lurch]

The hardness will depend on the alloy - obviously. To get the softest boolit possible in a given alloy, heat them to just below slump in an oven and then just turn the oven off and let them cool slowly. Then shoot them immediately. Lead alloys tend over time to seek their "natural" hardness level whether heated and quenched or just heated and allowed to cool slowly. I don't know what the timing is for annealed getting "hard" again, but for heat and quench, the alloy get hard over a week or two and then gradually softens over a relatively long period of time. I don't have the charts in front of me and it's been a while since I last saw them, but as I recall it takes a couple of years to soften back up from that state. Maybe someone with the charts will pipe up.

In any case, I would think using a low pressure loading would accomplish what you want to do regardless of the boolit hardness (within reason). A tight spot should smash the boolit down and anything beyond that point would see minimal effects if the pressure is low enough to not want to obturate the boolit.

[44man]

You want a boolit of 12 to 14 BHN, no softer or harder.
Air cooled or annealed WW's might be right. Depends on your WW's.
50-50 WW and pure, air cooled might be better.

[30hrrtt]

You could untemper yours according to "lurch" and it would work. Pure lead is too soft. Air cooled wheel weights works just fine. In the technical guide by Marshall Stanton of Beartooth Bullets, he recommends lapping bullets in the 10 - 14 BHN.

One other note. Make sure you done use bore-ride bullets to lapp. They erode too much of the lands compared to the grooves. You want then both to be lapped equally.

[30hrrtt]

44man beat me to it while I was typing.

Happy lapping.

[dubber123]

Posters 5 & 6 above are right on the money. Air cooled wheelweights works perfectly in the Bhn range mentioned. I have been doing ALOT of firelapping lately on revolvers. ACWW is working just fine for me.

[sqlbullet]

Put the bullets in an oven like you would to heat treat them. Heat them for 1 hour at 350°, then let them cool back down in the air. All heat treatment from quenching will be removed. The bullets will end up around a 10 BHN from typical WW alloy.

See chart here (http://fellingfamily.net/isolead/) at the bottom of the page. The rows with heat treatment = 'low' received this procedure.

[dubber123]

I had another thought, just in case you haven't firelapped before, and thats to keep the velocity low. You don't want much more than the bare minumum necessary to get the boolit out of the bore. High speeds are counter productive in firelapping. Good luck.

[outdoorfan]

Yes, just put them back in the oven at 350-400 for a half-hour or so, then shut the oven off and let them cool down. Once they're around 200 or so, you can take them out. BTW, the point where the HT'ing starts to happen is around 300 degrees.

They should be around 10 bhn after taking them out. If they are softer and need to age-harden back up to 10-11 bhn, then put them back in the oven for an hour at 200, and that will speed up the process.

[blackthorn]

Just curious here---fire (or any other kind of lapping ) is just an accelerated wearing process. You say this is a new, factory take off barrel. Why plan to lap it from the "git go"? Or do you plan to at least shoot it first to see if it really needs to be "lapped"? I would try it to see what it would do first---but its your rifle. Have fun and have a great day.

[RICKLANDES]

Just curious here---fire (or any other kind of lapping ) is just an accelerated wearing process. You say this is a new, factory take off barrel. Why plan to lap it from the "git go"? Or do you plan to at least shoot it first to see if it really needs to be "lapped"? I would try it to see what it would do first---but its your rifle. Have fun and have a great day.

ditto...why (potentially) fix something that is not broke?
I have lapped RB barrels with 0000 steel wool and oil so as not to have machine marks cut patches, but I have not seen the need with a regular barrel. I clean fire and repeat and increase the rounds between each cleaning as the shots fired increases.
Again, I have no desire to step on any one's toes, I guess I do not get why a fire lap is needed, especially when it sounds like you have a higher end firearm to begin with...I would have thought any lapping would be done by hand by the 'smith.

[CSH]

XWrench, let me say first off that I'm a huge proponet of firelapping. I've lapped about 20 of my personal firearms. Revolvers are almost always good candidates due to the high probability of a constriction just forward of the forcing cone. All of my revolvers have been lapped and most saw significant improvement in accuracy and leading reduction. Not all of them saw a significant accuracy gain, but none shot worse than before. I've also lapped a few autos and a couple of rifles. Be forewarned that depending on the diameter of the boolits used in the lapping, the throat of your rifle barrel could be enlarged to an undesired degree. I know this from experience with the first rifle, and as everyone knows experience is often a cruel teacher. Ever since then I've been a little wiser about lapping rifles and with the 2nd rifle only fired 6 shots with bullets sized to groove diameter. I would recommend that you try shooting the rifle first. Most factory barrels will shoot pretty well if the action is properly bedded (and all the lapping in the world won't fix a poorly bedded action). If (after glass bedding the action) accuracy is sub-par or leading occurs in a reasonable boolit load, shoot 2 or 3 lap shots, clean, then do a push through slug. Repeat the process until the slug slides through smoothly. This should not take very many shots unless the barrel is really rough.

The advice about alloy hardness and velocity is spot on. 12 BHN is perfect. Lapping can be accomplished with softer alloys but requires a lot more shooting to get the same results. Low velocity is a must when shooting unlubed boolits. Use just enough fast burning pistol powder to get them out of the bore. For larger rifle cartridges about 3 grains of BE should do the trick as long as the rifle is tipped prior to each shot to position the powder against the primer.

I echo the sentiments of RICKLANDES and blackthorn. A few jacketed rounds might be all that is required to smooth it for boolit shooting, or it might not need anything at all. Good bedding, good trigger, and THEN lap if required.

[XWrench3]

well, after reading all of this, i guess i am going to have to cast some new boolits anyways. as the boolits that i WAS going to shoot through it are bore riding nose boolits. didn't think about that before, THANX! i will now be using my 30-30 mold (the gun is a 300 win mag) so i will have to size them down from .311 to .309". i told the gunsmith to keep the chamber as tight as possible, as i was getting pretty short brass life before with it. another question, should i use gas checks on them, or just run them bare? two reasons for firelapping. 1) i want to shoot lead bullets through it right away, probably 80% of my shooting now is lead boolits, mainly because of costs. and 2) the original barrel on this gun took a while to "settle in" using jacketed bullets. meaning that the best accuracy took quite a few shots to come around.i dont think i want to start off with the really corse grit, all i want to do is smooth it out a little and get rid of the high spots. if i could have afforded it, i would have like to have had a hart or shelin barrel, but money does not come easily to me.

[dubber123]

No GC needed, use a small charge of fast pistol powder, along the lines of Bullseye, or Trailboss. I used Trailboss on my 45-70. 320 grit doesn't cut as fast as you'd think, and leaves a really nice finish compared to most factory barrels. Keep velocity low, and always check for a stuck boolit in the bore in case you go too low. Don't load a bunch up until you get the charge weight down. Ask me how I know...