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STP
03-20-2007, 09:21 PM
The Savage 340V .225Win I picked up recently is in dire need of firelapping. My friend just re-cut the crown for me, as my first visit at the range with somewhat reduced loads was dismal....nearly 4 inches of vertical with J-word bullets. I used 30.0 gr of IMR4064 under Speer 50gr TNT`s to keep the pressures down. (The single lug bolt is not a good design for this caliber.)
Cast is planned later on, but I thought I`d try the other bullets first as a baseline.
I borescoped it first and saw the pitting that the Outer`s bore foam revealed. (It took 4 or 5 soak cycles to remove all the copper fouling.) The foam is a real time saver! No brushing...I like that alot. But the pitting looks absolutely awful with the borescope. A blessing and a curse so to speak to have one of these available.
The crown was so bad, I preferred to have that corrected first. But even my friend commented afterwards "This is a candidate for firelapping". because he took a peek down the bore as well.
I have used the LBT firelap kit before on a Marlin 94 in .25-20 but the chamcer and bore was so bad the effort was wasted. I will borrow that kit again and will have to cast up some 14 BHN booilts to use with the kit. But I see NECO also offers charged J-word bullets already charged with lapping grit to accomplish the same task.
This begs a question to the board...has anyone else been down this road before, and what method did you use??
Grit charged cast boolits will require several rounds to acheive the desired effect, but will the NECO J-word bullets be as effective? I`m not interested in any shortcuts, but need some "been there, done that" feedback.
I don`t mind the effort, but would prefer to launch hard cast boolits at reasonable pressures rather that use J-word bullets at "safe" pressures.
I figure to coat the lapped bore with Moly paste to offset the resulting bore condition and give it a chance with cast.
Am I "coldpatching" New York State potholes, or do I stand a chance of reasonable success?

Bass Ackward
03-20-2007, 10:26 PM
What will work depends on where you are .... and where you have to go. If the jacketed lappers aren't big enough in diameter, then they will simply open the bore to their max and continue to eat the rifling height. On the other hand, the lead can open the throat if improperly done or the resistance is too high from the pits.

So if possible, I would do both. Start with a few copper to smooth up what you can and then go to lead at very low pressures. Of coarse, you will need to clean well after the copper.

How far you can go depends on your commitment. Open the bore too far and you need new molds and sizers and maybe you won't be able to chamber a big enough bullet when you are done. Maybe that means you can't ever shoot copper again.

So you need to slug and probably go with a chamber cast before hand to see if the journey is possible and exactly what you have to work with.

IcerUSA
03-21-2007, 12:48 AM
I have used a wooden dowel and lapping compound and done it by hand, but that was on a new barrel to smooth it up abit and get rid of the burrs and high spots, might also work for you if you don't have to take too much off. :drinks:

uscra112
03-21-2007, 01:06 AM
Gee Whiz, did they actually sell the 340 in .225 Win? I've got one in .222 Rem, which I consider reasonable, but lord, .225 Win in that action is like chambering a Krag for .30-06. Is this a .222 that was rechambered?

If the bore is pitted at all, firelapping won't do you any good. Won't take out enough metal, and will open up the throat something awful. The only known, provable benefit of firelapping is smoothing out a new barrel that's got too much in the way of toolmarks in it. In these days of button-rifled barrels, those are few and far between.

If you MUST lap the barrel, do it the right way, with a rod and a lead lap. Thing is, doing that in a .22 barrel is fussy.

Me, I'd clean the thing agressively iuntil I was 100% certain that I'd gotten ALL the copper fouling out of it. Any copper left in those pits will collect lead like crazy. Then I'd go shoot and see what happens.

If you want to try the Moly paste, give it a whirl. I'd like to know how it works out.

I've got an old Stevens .25-20SS, the bore of which looks pretty awful, but it still shot OK with Linotype boolits. The best loads were 1650fps and higher using a quick powder - 2400 to 4227 range. (My pet is XMP-5744, which is close to 4227) J-boolits it shoots like a house afire - 3/4" groups at 50 yards. Hasn't missed a single chuck I've fired it at, either. It hasn't been shot with cast for several years now, but I'd be interested to try it again with the Moly paste, if it works for you.

Bent Ramrod
03-21-2007, 01:41 AM
STP,

My firelap boolits are cast, not sized, and generally not lubricated, and I charge them with Clover 320 grit by smearing a toothpick full in a small patch on a steel plate and rolling the boolit through the patch with a steel strip. As the abrasive is used up, I renew the smear on the plate from time to time. I pack the boolits in a box, and take a big pair of tweezers and a dowel with me when I use them.

I usually select five cases to use for fire lapping and take them to the range with a de- and recapping tool, a box of primers, a box of abrasive-charged cast boolits and a powder measure set for a very mild charge of Unique or something similar. Generally I try to keep the shots at pistol velocities: 900 ft/sec or less. The abrasive charged boolits are placed as far into the chamber as possible with the tweezers and pushed with the dowel until they go no further. The unsized primed case is held under the powder measure and a pre-measured charge thrown. The case is then loaded and fired. I usually fire at a target at 25-50 yards. I then de-and recap, refill with powder and continue.

Every five shots, I clean the chamber and bore with patches with WD 40, and then scrub the bore with a bronze brush. If I don't use the brush, I find that the roughest parts of the bore get the heaviest coating of lead, which protects them from the polishing that they need the most. I also check the holes in the target for grouping. Generally I see some rough index of improvement in the course of a lapping session. If I'm really wondering whether it's real, I'll bring some "real" ammo along and fire five shots (after careful cleaning) to see if things are doing better. I keep wiping the lapping cases off, cleaning the chamber and making sure the abrasive is pushed out the end of the barrel, and doesn't run backwards into the action. If I'm not sure of this, I take the gun apart when I get home and spritz it out with WD 40 and wipe it down.

Generally in these sessions, I'll fire from 20 to 50 shots, and with some really refractory barrels, I'll do multiple sessions. The effects of this treatment have varied from no improvement in accuracy (but easier to clean) to quite marked improvements. I've never had worse accuracy result from this treatment, but of course, I've never lapped any barrel (fire or otherwise) that shot well in the first place. I've also never kept the fire lapping up in hopes of getting a 2-1/2" grouping ability down to benchrest standards; a reasonable improvement, especially the elimination of flyers, is enough, I figure.

If I've increased freebore or washed out a leade by doing this, it's never hurt anything that I can see. It seems in many cases that some of the blame for a rifle that throws them around might be a bad throating job, with roughness or burrs. I guess you could continue with finer grits, but I've never done this.

Hope this helps. Go slowly and check your results. You can always stop, fire a box of ammo for groups and decide whether to continue lapping. Throw away the lapping cases when you're done with them so they don't get back in with the rest and lap your resizing dies by mistake.

MT Gianni
03-21-2007, 09:37 AM
Be careful with WD-40 as it is a rust remover and bluing is a rust. Make sure it only goes in the bore. Gianni.

schutzen
03-21-2007, 02:41 PM
One thing I have used on bad bores it to plug the breach with a cork or rubber stopper, fill the bore with cheap penetrating oil, and let it set up right for 24-48 hours. Dump the penetrating oil out. Clean with an aggressive brush and a good bore cleaner. This works very well to loosen any scale in the barrel. Try it; you will be surprised what comes out of a "clean" barrel. This technique works particularly well on muzzle loaders that have been left with powder residue in the barrel.

lovedogs
03-21-2007, 07:07 PM
Nothing to do with the fire lapping ideas but I hope you don't try those TNT's at regular .225 velocities. They're meant to be held down to .223 velocities. At high speeds they usually come apart and never make it to the target. They are thin jacketed and made with soft, scored copper. Sometimes an exceptionally smooth bbl. will shoot them but they weren't meant for this kind of duty.

slughammer
03-21-2007, 08:05 PM
STP,

.... I pack the boolits in a box, and take a big pair of tweezers and a dowel with me when I use them.

I usually select five cases to use for fire lapping and take them to the range with a de- and recapping tool, a box of primers, a box of abrasive-charged cast boolits and a powder measure set for a very mild charge of Unique or something similar.....

Bent Ramrod, that is an excellent write up and a bunch of new ideas for those of us that fire lap.

Thanks a bunch for sharing. This post is getting saved.

STP
03-21-2007, 09:20 PM
Thanks much for all your comments.

The 340V`s first visit included reduced loads...I know better. This caliber didn`t last long in their lineup. The Win. M70 was the only other rifle offered in .225Winchester. The cartridge came out just prior to Remington`s first factory loaded 22-250, a popular wildcat at the time that was tremendously popular. That signaled the end of the .225Win...
I often wonder how many 340V`s came back to Savage with split lugs, or worse!

While I don`t have illusions about the bore NOT increasing in size by firelapping, I will proceed with due caution. I will slug the bore first...then use the CerroSafe for chamber casting.
I checked the bullet to throat dimension last night with the Stoney Point OAL tool with a Sierra 55gr SP and was stunned by the outcome. Let`s just say it`s waaaay out there....2.718! That introduces another uneeded variable eh?

To repeat, I was able to get ALL the copper out using the Outer`s bore foam. I plan to leave just a trace of ED`s Red in the bore prior to shooting the lap bullets so as to ease the bullets passage down the bore. Don`t need to leave lead deposits behind from the get-go as I can`t use lubed bullets for the process.
I followed LBT`s instruction sheet to the letter by using but a few cases and loading as recommended when I attempted this "fix" with the Marlin 1894. For sure, the barrel sure won`t get warm during the range visit.
I also will be sure to have the borescope with me to check the progress. Probably will take a peek after each 5 rounds. I should slug the bore between the 5 shot groups as well so as to not go too far too soon. Don`t want a .22 Savage High Power! (.228 groove diameter) Anyone know that one`s working pressure?

Hopefully, this will proceed at a reasonable pace.

Again, thank you for the replys.

Lawyerman
03-22-2007, 12:07 PM
Heres another possibility, something I have done with pitted milsurps......Cork the chamber end and pour the barrel full of Outers Rust and Bluing Remover and let it sit for a half hour. Then clean well. Be careful with this stuff obviously as it will take the bluing off.....Good luck.