Firelapping time!!!

[405 WCF]

Now, lets see!
I have cast some soft 350 grs bullets,( aircooled ww ) for my 405 wcf.
Unsized, just sat the GC with the fingers.
"lubed" them with Valve Grinding Compound, ( Carborundum ).
I have loaded them with 25 grs VV N120, and filler.
I guess that they will leave the barrel at around 1000 - 1200 fps.
Is that to fast?

[bishopgrandpa]

YES!! Go to Beartooth or Veral Smith to learn more. I understand the boolit is to be moving just fast enough to leave the barrel. I have success with that. Marshall will keep you straight on that.

[VTDW]

Olle,

That is waaaay to fast bro. You want the boolits to just make it out of the barrel. Somewhere on Marshall's site there is an article about firelapping that tells you how much powder to use though it is not VV. VV will work just tone down your load. Try 5 grains in a dummy round and see what happens.

Dave

[k8bor]

I would try about 5-6 grains of unique or some similar load. you should be able to see the bullets come out of the barrel. Mine always have more of a "poooonk" sound when I do mine, and the bullets hit the ground or whatever I'm shooting towards with a "thud".

Try not to get over 500-600 fps. I even stick one by the muzzle every so often, but just coax it the rest of the way out with a brass rod.

k8bor

[rroberts]

Marshall recommends 500 to 600 fps max. He says any faster and it isn't working very well.

[Whitespider]

Valve Grinding Compound? I’m assuming we’re talking about “Valve Lapping Compound”.

Can ya’ really use that stuff to “Fire Lap”? I would think it would be a bit course, but I’m always willing to learn new tricks. Tell me.

[Diamond-City-Bob]

Drop back to about THREE grains of Red Dot Ideally the bullet will fly out the end of the barrel and fall to the ground about ten feet out.

[BABore]

Clover Lapping compound is highly recommended because of the type of abrasive and the carrier oil. I think Marshall calls for 320 grit.

3-4 grs. of Red Dot and a little tuft of Dacron to hold the powder against the primer. I would do away with the gas check altogether. Seat the bullets in reprimed, UNSIZED cases. Clean completely at least every 4-5 shots and check progress by observing the rifling tooling marks at the muzzle end. Stop when you just see them start to clean up. Most all my rifles took 24-36 rounds. Usually chickened out at around 18 rnds, tried it out with a normal break in, then went another 6-18 FLing rnds. Better to go slow.

[Boomer Mikey]

Clover Lapping compound is highly recommended because of the type of abrasive and the carrier oil. I think Marshall calls for 320 grit.

3-4 grs. of Red Dot and a little tuft of Dacron to hold the powder against the primer. I would do away with the gas check altogether. Seat the bullets in reprimed, UNSIZED cases. Clean completely at least every 4-5 shots and check progress by observing the rifling tooling marks at the muzzle end. Stop when you just see them start to clean up. Most all my rifles took 24-36 rounds. Usually chickened out at around 18 rnds, tried it out with a normal break in, then went another 6-18 FLing rnds. Better to go slow.

Good answer BA!

It's very important to check after every shot at first to remove any leading with a Chore Boy until there isn't any lead in the bore after each shot otherwise you're not working on the spots in the bore you want to most. Use BHN 10-15 bullets as they will size themselves down to work only on the constrictions. Hard bullets will have more "spring back" working on the entire surface of the barrel smoothing it but not removing constrictions. The same with soft bullets... obturation will work the whole surface too and this is the reason for minimum velocity... you don't want the bullet to obturate. Powders that aren't position sensitive and ignition sensitive like bullseye, unique, tite group, trail boss, clays, 700X etc. are best with no filler required and this is a good time to use all those junk primers that seem to accumulate from time to time. I use 3-5 grains of tite group, 5 grains in the big cases and a bullet with as much bearing surface as I can get that's at least 0.002" larger than groove size. Embed 320 grit lapping compound (clover) into the bearing surface of the bullet by rolling the bullets between two steel plates coated with the 320 grit Clover lapping compound. The more you embed into the surface, the faster the job gets done, it's ok to have extra compound in the grease grooves but not necessary, the embedded surface does the work. Wipe out the chamber after each shot to prevent scoring by the compound blown back into the chamber and action as cases don't seal well at this velocity. This is a lot of work but well worth the effort.

Boomer :Fire:

[405 WCF]

The fastest powder I have at home is VV n120, and powder is NOT cheap here in Sweden, so just buying a bottle of fast burning powder, just for the lapping, is to expesive for me.
I will try to load very slow with my n120.
Thank you for all the info you have posted.
I will allso order some better lapping compound.

[Bass Ackward]

The fastest powder I have at home is VV n120, and powder is NOT cheap here in Sweden, so just buying a bottle of fast burning powder, just for the lapping, is to expesive for me.
I will try to load very slow with my n120.
Thank you for all the info you have posted.
I will allso order some better lapping compound.


405,

Also keep a light coat of oil in your bore between shots so that the slug doesn't load up and quit cutting causing you more wear at the throat than you want. Firelapping will take fewer shots to reduce minor problems and minimize diameter changes. And you cut the risk of sticking a bullet in the bore.

[tom barthel]

I used about 3.5 grains of unique. I ordered lapping bullets from Beartooth. I rolled a few in the glovers compound and pushed them into the cases with my fingers. I don't recall the number I think, 15-20 rounds. I wanted to be sure of ignition so, I stuffed a small wad of cotton against the powder. I used a 3/8 dowel rod to punch out about three rounds in all combined. I did my 1894 marlin, my .444 and my .45-70. It seemed to help. If in doubt, call or e-mail Marshal Stanton at Beartooth. I also ordered his book on the method. I'M satisfied with MY results.

[fourarmed]

I just discovered recently that charging an oversize boolit with grit makes it even more oversize. There I was, stuck with 12 358429s seated 'way out in 357 mag cases that refused even to start into the chambers of a Ruger maximum. In my usual calm reaction to such an event, I threw a hissy fit and started to trash all of them. For some reason, I resisted these base urges. A few days later, I ran across a Lee 357 Factory Crimp Die in my major award box. I ran them through it, leaving the front two bands full diameter (they were out of the case) and they chambered easily. Amazing what you can learn at an advanced age.

[uscra112]

Allow me to throw a bucket of ice water into this thread.

There's an awful lot of hokum being promoted for firelapping. On par with Global Warming and Carbon Offsets, IMHO.

Unless all you want to do is open up the throat and first 6 inches of your barrel, there is NO safe speed for firelapping.

Firelapping MIGHT do some good for a barrel with roughness in that first few inches. Otherwise, it's the quickest way I know of to ruin a barrel.

None of the expert Scheutzen barrel-makers like Schoyen or Pope would have had another word to say to you if you'd mentioned firelapping on their presence.

Seriously - there was a careful study of firelapping published in the Rifleman, years ago when it was still possible to write about actual gunsmithing in the magazine without causing lawyers to salivate. They did very careful measurements of the results, and it was clear that the process did no good at all for the barrels they tried, and that most of the metal removal came in the first 6 inches in front of the chamber.

If you MUST lap a barrel, it has to be done properly, with a rod, to accomplish anything good. Even then, the process cannot be carried very far, since it inevitably wears the sharp corners off the rifling.

If all you want to do is POLISH a bore, shoot a few hundred paper-patch boolits throught it.

[Bass Ackward]

Allow me to throw a bucket of ice water into this thread.

USA,

Every time you run a bullet of any material down a bore, you in fact are fire lapping. Why old man Shilean said the only difference in the two grades of his rifles where the best grade is hand lapped was 50 shots. Amazing admission from a then top manufacturer.

Whether you have any grit or not, whether that bullet carries lube or not. In fact, there are lubes that have poor (or no) lubrication properties that can actually fire lap better than fine grits with cast. And there are lubes that have ingredients in them that actually increase wear too. Heck, the use of cast bullets under best conditions, because they polish powder impact, will cause more throat wear and put a taper in your throat for a few inches if you use antimony. Especially if you shoot over bore diameter. (like to choke.)

You CAN fire lap with commercial (idiot proof) systems today that will remove no more than .0003 and create no taper at all. It might surprise you that some long range shooters of jacketed fire lap every 500 rounds or so finding that it actually EXTENDS barrel life by remove microscopic cracks in the steel that form in the throat from hot powder. Some guys like to alternate between copper and lead every so often (me).

I have fire lapped well over 100 rifles and handguns. I would say 20% had improved accuracy with the same ammo. Another 60% had improved accuracy, but the loads had to be tweaked. (big surprise) And probably the last 20% didn't show enough improvement (other than cleaning) to make it worthwhile. And only one was ruined, that had to be replaced, because I was experimenting on just how much was "too much" before improvement should / could be expected.

IMO, of the people that fire lap and "did not see" enough improvement, 50% stopped before they got to the promised land out of fear or they weren't monitoring and ruined their dimensions with improper technique. After all that, some simply fell into the 20% where "it didn't matter too much" category because they had other problems. Happens.

Of the people that ruin a gun, 90% will go to their grave blaming the process instead of THEIR failure to monitor and either alter technique or STOP.

Low pressures / velocities, slugging often, and oil in the bore so the slugs doesn't load up and stop cutting (put in a taper) are the keys. But there are many, many other tricks too. :grin: But your post does serve as a warning to make him think. Thanks.

Actually slugging often should be done anytime you shoot cast just to make SURE you aren't .... fire lapping for some reason.

[BABore]

Allow me to throw a bucket of ice water into this thread.

There's an awful lot of hokum being promoted for firelapping. On par with Global Warming and Carbon Offsets, IMHO.

Unless all you want to do is open up the throat and first 6 inches of your barrel, there is NO safe speed for firelapping.

Firelapping MIGHT do some good for a barrel with roughness in that first few inches. Otherwise, it's the quickest way I know of to ruin a barrel.

None of the expert Scheutzen barrel-makers like Schoyen or Pope would have had another word to say to you if you'd mentioned firelapping on their presence.

Seriously - there was a careful study of firelapping published in the Rifleman, years ago when it was still possible to write about actual gunsmithing in the magazine without causing lawyers to salivate. They did very careful measurements of the results, and it was clear that the process did no good at all for the barrels they tried, and that most of the metal removal came in the first 6 inches in front of the chamber.

If you MUST lap a barrel, it has to be done properly, with a rod, to accomplish anything good. Even then, the process cannot be carried very far, since it inevitably wears the sharp corners off the rifling.

If all you want to do is POLISH a bore, shoot a few hundred paper-patch boolits throught it.


All well and good. But now tell us all, exactly how many barrels have you firelapped yourself? What method did you use, type of abrasive, bullet hardness, velocity? What were the before and after test groups like.

I would never recommend firelapping a quality custom barrel. Most of us firelap to smooth bore's and remove constrictions on stock barrels. I have personally fire lapped seven rifle and pistol barrels. In every single case there has been a vast improvement in accuracy and ease of cleaning. Everything was documented before and after. First hand results trump 2nd hand BS every time.

[VTDW]

Taking an article like that is as fact is like reading Golf Digest and expecting to improve your golf game 10 strokes.

What amazes me is the naïveté of some posters in lieu of facts presented. I have found in my life that I remained ignorant about some subjects because of my close mindedness. This thread makes me read various articles and weigh certain things such as who wrote them, who they work for, am I being presented pure facts us supposition, can I sense a bias and etc. I was sitting in the Dr's. office yesterday and picked up a Field & Stream and glanced thru it. WOW!!! Here is an article on hawg hunting! I read the darned article and was amazed at the ignorance of the author and also included was a section on What You Need To Hunt Hogs. Purely salesmanship and to heck with accurate information about hogs. The author missed the number of states with feral hog populations by six. He missed the best place to aim for a clean kill shot with a rifle by about a foot. He missed the best place to aim for a clean kill with a bow by another foot. He missed badly the estimated numbers of feral hogs. He said the feral hog's vision is very poor (bullsh$$t). The list goes on but to the uneducated (about hunting hawgs) this article seemed accurate and would make one go out and purchase a bunch of gear that is not necessary or even will not work.

Oh well, let the games proceed. :drinks:

Dave

[Boomer Mikey]

I originally got into this fire lapping stuff after the purchase of three Ruger SS M77 MKII's that had corncob barrels... it was impossible to shoot 3 shots of Jword bullets without cleaning for an hour or more. I tried the Tubb kit and was satisfied with the results as cleaning became a breeze and fouling was virtually nonexistent with an improvement in accuracy to one moa from 3 moa. My Marlin 1895 45-70 Cowboy was slick as a whistle out of the box and has never required more than a few patches to clean, it's also a one moa rifle.

Most of the bad breath about fire lapping is related to the bench rest crowd. We're talking about production firearms and lead bullets, not air gauged barrels with custom chambers; about as different as apples are from bananas.

Books written by Marshall Stanton and Veral Smith lay out the purpose for, and methods for improving a lousy situation for cast bullet success in production firearms with documented results. What are the options? Use a lousy barrel with lousy results? Have the gun re-barreled? Order a custom made rifle? Or tinker around and obtain satisfactory results with an investment of a little time.

This is a cast bullet site, I would venture that most of us that have tried to make an otherwise useless (for cast) rifle better by fire lapping or hand lapping would say it improved the situation. Fire lapping my Rugers certainly did. Anything done improperly can destroy or make things worse but I'll bet more firearms are ruined by improper cleaning than fire lapping. Of course this isn’t a blanket endorsement for the process; I wouldn't consider fixing things if they weren't broken.

Each shooting discipline has its basic methods and practices and fire lapping is a topic worthy of caution but if you haven't tried it in the context of the discipline under discussion (cast bullets in production firearms) then you lack the understanding to disapprove of the practice. I don't consider Scheutzen rifles to be production firearms and I would bet that Schoyen or Pope would never own one that had a constriction at the chamber end of the bore.

I guess we’re back to the apples and bananas,

Boomer :Fire:

[Yukoner]

I am about to firelap a Husqvarna Model 46 in 9.3X57 that has a somewhat darkened bore. It shoots jacketed just fine, but I would like to start shooting cast in it.

Intend to start with Clover "Fine " lapping compound. Any suggestions or heads up?

Thanks,
Ted

[Bass Ackward]

I am about to firelap a Husqvarna Model 46 in 9.3X57 that has a somewhat darkened bore. It shoots jacketed just fine, but I would like to start shooting cast in it.

Intend to start with Clover "Fine " lapping compound. Any suggestions or heads up?

Thanks,
Ted


Ted,

Really, you haven't said anything above that would tell me that I need to fire lap. Lead is a polisher anyway. Much more so than copper. Personally, I would try about 50 low velocity stuff with hard bullets and then clean and see what I was looking at. Then determine method.

If you want to fire lap right off, then I would go with a Tubb's Kit as it won't affect dimensions much at all.

[45 2.1]

I am about to firelap a Husqvarna Model 46 in 9.3X57 that has a somewhat darkened bore. It shoots jacketed just fine, but I would like to start shooting cast in it.

Intend to start with Clover "Fine " lapping compound. Any suggestions or heads up?

Thanks,
Ted

I wouldn't. I have the same thing. I fireformed 150 cases with ground corn cob over some red dot. The bore is glass smooth and polished after those corn cob loads. Give it a try. Amazing results....!

[MT Gianni]

I agree with BA & 45 2.1. At the very least you want to establish a base line by firing enough lead to measure improvement. Gianni

[PineTreeGreen]

I used the corn cob case polishing media to polish a .357 Max barrel. It didn't seem make any differance in how it grouped but sure made it a lot easier to clean. The bore was mirror bright. It probably took 75-100 rounds:-D

[Yukoner]

Okay, that all makes sense. Thanks!

Now, any thoughts on a mold for the 9.3s? That will be my next pursuit.

Ted