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primersp
05-14-2011, 04:49 AM
hello
did you size and grease the bullets before rolling in abrasive compound?

THANKS

btroj
05-14-2011, 07:58 AM
Nope. You want fat bullets. No lube either.

303Guy
05-14-2011, 08:12 AM
No lube? I can't say which is better but the method I use uses wet grinding paste. I suppose it's a toss up between wet sanding and dry sanding. I would have gone with lubed then rolled in grit but no sizing. That doesn't make me right! Maybe I'll try dry rolling on an un lubed boolit. Paper patched boolits are essencially lubed by the paper and that is my 'normal' polishing lapping method. Dry cast might be a lot easier. (I haven't done a hell of a lot of it so my experience there is limited).

btroj
05-14-2011, 09:38 AM
I take bullets cast soft, right from the mold, and roll them in my lapping compound.
I suppose this is one of those " I do it this way just because I do" type of things. Can't say I have given it lots of thought.
I have read where others have lapped a revolver barrel by shooting low velocity loads that were loaded normally but they put a small amount of the grit compound directly into the throat of the barrel.

Anyone out there ever compared results of using a dry bullet rolled in lapping grit to one that was lubed normally first then rolled in grit?

Brad

XWrench3
05-14-2011, 10:56 AM
are you lapping a revolver, or a rifle?

primersp
05-14-2011, 12:19 PM
i want lapp an rifle an ruger 77 in 257 rob ,i have only some bullets cast and lube and a neco kit , second hand buy on a forum ,no manual the 4 jrs of grit and the 2 plates
i must use that bullets ( cast 258 and gc )because i have trade the mold or jkt
i plain to shoot 5 of each grit .

gandydancer
05-14-2011, 12:29 PM
get the technical guide on fire lapping by J.Marshall stanton from Beartooth Bullets. www.beartoothbullets.com it will tell you all you need to know. gandy

gandydancer
05-14-2011, 12:36 PM
I am looking for a no longer made Lyman bullet mould from the 50's--60's lyman bullet no #429303 designer was C.F.Hudson any info will help. thanks. gandy

Russ in WY
05-14-2011, 01:15 PM
Primersp , You mite try the Neko website for info on how its done .. I did a .224 many yrs ago & got very good results, it was fouling very bad even with coated bullets . The one point that the did say unless it was an "Extreme" problem of fouling , to skip the 1st [coarse] of grit . Mine was extreme so i used all the bullets , I had the precoated bullets from Necko. All I did was load according to directions & fire the loads . use a low velocity for the fire lapping. Also for the last[Fine Grit] loads fire at least 10+ rnds , as this is the Polishing part of the process... good Luck , it work great for Me & improved the Grouping also .. Viewing with a Bore Scope after the process , [Did Not ] show the erosion of the throat as many say it will do . Good Luck Russ.

markinalpine
05-14-2011, 01:18 PM
Here's a thread I started that ended up going on a lot longer that I expected: http://castboolits.gunloads.com/showthread.php?t=102711&highlight=garza
and here's the article I cited with some good info on fire lapping. The author was talking about his process for revolvers, but a lot of it could be applie to rifles too: http://www.gunblast.com/FerminGarza-Firelapping.htm

Mark :coffeecom

Larry Gibson
05-14-2011, 02:25 PM
primersp

I also have the NECO kit. PM your address and I'll mail a copy of the Instruction Manual.

Larry Gibson

geargnasher
05-14-2011, 06:39 PM
It will likely take more than five.

Why, may I ask are you choosing to firelap?

Gear

primersp
05-15-2011, 02:09 AM
i will fire lap because the gun isn't an tackdriver ,i have make bedding ,crown the muzzle ,
no accurcy with cast bullet ,with jkt and following the hornady reloading data ,i shoot
1 to 2 inch at 100m.
it's an ruger 77 tang safety and i have read in forum that accuracy with these barels is often an lotery

badbob454
05-15-2011, 02:17 AM
is this your boolit mold ? you are looking for ?
http://shop.ebay.com/i.html?_from=R40&_trksid=p5197.m570.l1313&_nkw=429303+lyman&_sacat=See-All-Categories

303Guy
05-15-2011, 02:35 AM
primersp, I cannor give advice on fire-lapping but have you exhausted all other 'tricks' to get accuracy with cast? Like taking a throat cast and tailoring the boolits for your gun?

Do you get leading with cast? Does your rifle bore show much copper fouling when shooting jacketed bullets?

I would tend to agree with you on your approach and I might even do the same. So far I have only fire-lapped rust damaged bores. I did not see any obvious throat erosion from the process but even if I did I would not worry because it would mean a bigger boolit and less neck sizing. But that's just me.

geargnasher
05-15-2011, 01:15 PM
Personally, I doubt firelapping will improve accuracy in that case.

Firelapping is used to smooth rough, uneven, or restricted bores, which helps accuracy indirectly by reducing lead and powder fouling during long strings of shooting.

If you aren't experiencing excessive lead or powder fouling, look to other methods to improve your accuracy first.

1-2 inches at 100M isn't all that bad, so simply a change of seating depth or boolit design, or slight adjustment in powder charge might improve some.

Gear

primersp
05-16-2011, 08:17 AM
the only thing that i remember the barrel of this rifle is skiny sure ,but become very hot in
5 shoots .
thanks for yours advices ,i will try others reloads before lapping

cheers

Bass Ackward
05-16-2011, 10:44 AM
With one of the older Ruger's, the problem can come down to the proper bullet design to act as a guide for an EXTREMLY large throat.

How large can it be? Worst I have heard of was a fella with a 284 bore having a .300 throat that was .335 long.

Reach across that divide with a proper bore ride of some sort and accuracy was achieved. So you are going to have to read about slugging a throat. Use the search function and TONS of stuff will pop up.

If you need to create something special after doing that try here:

http://mountainmolds.com/

Doc Highwall
05-16-2011, 01:26 PM
Some times the rifle is not at fault, it is the scope not holding a zero causing the groups to open up. Have you tried a different scope?

Larry Gibson
05-16-2011, 03:14 PM
Copy of the NECO instruction manual was mailed to primersp today.

Larry Gibson

303Guy
05-16-2011, 06:05 PM
... but become very hot in 5 shoots. I had a load for a 22 hornet - quite a powerful load - that heated the barrel something fierce. Then one day I increased the powder charge a small amount and the barrel heating stopped. The powder was Lil'Gun. I've no idea why that is but try changing something to see what happens. That barrel heating can't be doing accuracy any good. It's not the barrel itself that causes the heating (other than normally expected heating). My hornet was equally accurate with both loads but that was j-word bullets and it does have a rusty bore.

Have you thought of paper patching? It's a good way to polish the bore and also to fit the throat if it's a little large. It also allows you to shoot at near full rifle velocity with faily soft alloy. Just a thought.

nanuk
05-16-2011, 08:31 PM
have you cleaned out all the copper before trying cast?

I have read that some barrels are affected badly by copper fouling when shooting cast.

primersp
05-17-2011, 04:59 AM
before lapping i try some others loads and bullets ,for this rifle i have trade the mould and i have just some 200 cast rcbs 100grs g.c. size to 258
the barel was clean solvant, brush and flitz to finish .
the scope was new an burris 3x9 .
i am not lucky with cast bullet in only 2 rifles an brno fox in 22 hornet ,but shoot well with jkt
and this ruger

Bass Ackward
05-17-2011, 06:34 AM
i am not lucky with cast bullet in only 2 rifles an brno fox in 22 hornet ,but shoot well with jkt and this ruger



The purpose of a throat is to guide the bullet into the bore so that it can establish bore and bullet center which should be the same.

The hard bullet (jkts) that is shaped to do that itself is working properly.

The softer one (cast) that is probably NOT shaped to find center is having more difficulty. Sometimes a softer bullet needs to be a larger diameter to accomplish that itself.

The very first step with cast is to slug. One step is the throat slug. The throat slug will provide information on cast bullet / mold selection, correct diameter needed, and for selecting and seating jacketed bullets as well.

Better to know what you have than to guess. Your statement above says you don't guess very well.

XWrench3
05-17-2011, 07:26 AM
i think a lot of people are afraid to try firelapping, for fear of ruining a "perfectly good" barrel. and i can certainly understand that. it is a lot of money to be playing around with. most guys would simply rather sell, or trade off a gun that does not shoot correctly out of the box. my 45/70 marlin, had such a rough bore, that it would litterally SHRED a cleaning patch after 4 or 5 passes down the bore and back. the copper fouling was atrocious. i bought a kit from midway, a david tubbs final finish system. it worked wonders on the bore. it was the absoloute best thing that ever could have happened to that barrel. cleaning patches now glide through the barrel like a mop on a polished granite floor. it did help the accuracy some. but it did not turn a mo"barn" barrel, into a moa rifle. it is pretty close to that now with factory loads, and i have 2 loads so far that will deliver moa groups, IF i shoot them from a cold barrel. bottom line is, if i had a rough bore, or one that will not shoot straight, i would definitly try firelapping.

primersp
05-17-2011, 10:39 AM
BASS ACKWARD
you suggest to slug an soft lead or make an cerrosafe print?

Larry Gibson
05-17-2011, 11:59 AM
primersp

When you get the instruction manual read it carefully and you'll understand what fire lapping can and can't do for the rifle. With most milsurp and regular factory rifles barrels that I fire lap I use the fall back method described in the manual. It is easy to do and has always shown an improvement in reducing fouling and/or improvement in accuracy. I've not had any barrel shoot worse after correct fire lapping with the NECO kit nor have I heard of one. Other methods have their own results, good and bad.

With commercial rifles, especially sporters, once you get down to the 1 moa range of accuracy (I'm talking consistent 5 or 10 shot groups, not the occasional good group especially those 3 shot wonders), with cast bullets, trying to make further improvements in accuracy that are consistent can be just a dog chasing his tail.

Larry Gibson