Fire lapping experiance results.

[barrabruce]

O.k. I think I want to fire lap this bore in my 30-30.

Its start of the barrel is dullish compared to the rest of the barrell.
There are some dings and things on the start of this as well.

Since I have been PP ing it has smoothed out the barrell quite a bit. More ore less taking a tight spot out and most of the chatter maks in the start of the rifling from when I got it.

I wanna open up the diameter a bee's dick and smooth and open the start on the barrell say about 4-6 inches from the chamber.

A tight dry patch will squeek down the bore till the last 4 inches or so to the crown and it opens up slightly there. Sort of the barrell the way you'd want it fitted back to front.

Will fire lapping cure this.....lap out the first section more than the muzzle???

If so what git sizes you recommend and loads.

Or would I be better off just enjoying it the way it is.

Or hand lapping it out???

I was getting good accuracy from factory ammo today 1 1/2 moa roughly and about 2 1/2 moa with PP. Plain cast good as I could hope for.

Its reasonable accurate and I am happy with it, but I believe it has more potential there to be made use of.



Barra.

[docone31]

What I do,
Depending on what the barrel slugs out at, I patch .001 more than a jacketed load.
For example, .308, I patch to .309. This I lightly smear valve compound on the LOADED round.
With my .303 Brit, I fire .312s, When I paper patch, I use valve compound on .313, regular patch at .314.
Some where in there is a rough guidline.
I hope it helps.

[Zeek]

Stick with "fine" or grits 400 to 600
(Brownells: http://www.brownells.com/.aspx/sid=4...pping_Compound ). Avoid the coarse stuff (less than 400 grit), for it will move your rifle's throat forward measurably! The fine stuff behaves itself.

Docone31's approach should work nicely.

Another approach requires regular CBoos (GC & lube groove) around 0.001" over groove diameter. Smear the valve grinding compound lightly across one flat piece of steel and then put the CBoo on it and roll it across while pressing down lightly with another flat piece of steel. Wipe all loose grit off each CBoo so processed. You'll see that this embeds the grit into the surface of the CBoo (the surface looks like it is starting to grow hair!). You can handle and seat these babies just like the non-lapping CBoos, because the grit will NOT leave the CBoo's surface (so will not foul your seater die, for example).

For this type, use a light charge ~~~>for most military mid-caliber chamberings, five grains of Unique works nicely. Try a dozen rounds then push through a tight patch to feel the results. Also look down the bore. Fire no more than two groups (24 rounds) for, if that doesn't "do it" then firelapping is not going to be the answer.

The majority of the material removal focuses upon the tight places and rough surfaces in the rear two thirds of the barrel. A trumpet-mouthed barrel will not get cured with firelapping, but that bad part just ahead of the chamber should be amenable to improvement.
Let us know how it goes,
Zeek

[RobS]

I am weary about valve compounds has there are different grits for sure and many times the grit size isn't even noted on the products. Some fine grit valve compounds are 160 grit which is very course for a barrel IMHO. Course valve compound can be as rough as 80 grit (ouch to your barrel for sure). If you can find a grit that is labeled in the 300's or 400's you can worry less about taking too much metal from your bore or just plain up ruining the bore because of a too course grit compound.

I may be a bit over precautious but it is better the way it is currently if you happen to go and ruin it with a valve compound that you don't know what the grit is.

FWIW

[geargnasher]

I just recenly firelapped a .30-30, here is a quote from Mr. Brandt of BRP bullet moulds. I couldn't have had better instructions from a book:

(Quote) You want 500-600 fps.

I try to use a boolit with alot of bearing surface and preferrably not a bore ride type. A GC boolit, sans GC, is fine. Use a 11-13 bhn boolit cast from straight WW's as cast. Coat the boolit with a gob of Clover 320 grit and roll between plates til it is embedded good. The bands should look black. It should take you 2-3 minutes to coat one boolit. fill the lube grooves with compound. Clover brand lapping compound is silicon carbide suspended in a heavy grease. It breaks down into smaller grits as it goes down the bore. The ACWW boolit will get sized down as it passes under a constriction and wears it away. The lapping process works progressively from breech to muzzle.

Use unsize cases that were fired in your gun. Extend out the decapping pin and deprime them, then reprime. Use about 2 grains of something like Red Dot and put in a tuft of Dacron to keep the powder close to the coals. Gently seat the boolit and try to not drop it in the case. Try one and make sure it exits the bbl. Shoot 5 and clean completely, then repeat. I initially clean the gun and inspect the grooves at the muzzle from an angle. Take a pic if necessary. You need to know what the tooling marks and rifling look like. When the lapping proceeds to just, and I mean just, start to abraid on those marks, STOP. I have found that most all the rifles and pistol I've done take between 25 and 35 lapping rounds total.

Now, clean the bore well. Then, take an old bronze bore brush and wrap it with a long strip of cotton. I use an old pair of skivvies and cut a 12 wide strip from below the waist band. Wrap the brush til it is a very tight fit. Coat it well with lapping compound and push it from breech to muzzle and don't leave it come out either end once it's in the bbl. This back and forth is one stroke. Do 99 more in rapid succession. When done the bbl will be warm. Clean it one last time and you will freak at how smooth it is. I then break it in as you would a new gun

I've done many guns like this as well as having shown others. I've never had it fail to improve accuracy. Usually drastically. Everything I've stated here is as I've digested it from the Beartooth Bullets manual. LBT's instructions are similar.
(end quote)

Sounds like exactly what you need to do to recover the correct bore taper. As the grit breaks up in to finer pieces the amount it cuts decreases, so the most work is always done at the breech end.

One note on velocity, I tried several lapping charges and found the one that worked the best left a wet "lube star" of valve grinding compound on the muzzle and a wet look to the bore.

Gear

[geargnasher]

I am weary about valve compounds has there are different grits for sure and many times the grit size isn't even noted on the products. Some fine grit valve compounds are 160 grit which is very course for a barrel IMHO. Course valve compound can be as rough as 80 grit (ouch to your barrel for sure). If you can find a grit that is labeled in the 300's or 400's you can worry less about taking too much metal from your bore or just plain up ruining the bore because of a too course grit compound.

I may be a bit over precautious but it is better the way it is currently if you happen to go and ruin it with a valve compound that you don't know what the grit is.

FWIW

That's why you buy Clover brand compound, you know what you're getting. 320 is all I used on the above rifle, same stuff I've used in revolvers. Due to how it breaks down I've never needed anything finer for finishing, I feel that the scratches 320 leaves hold lube like the crosshatch marks on the cylinder walls of a reciprocating engine.

If the gun is destined for paper-patch boolits, they will polish the bore to a mirror shine anyway so no need to firelap finer than 4-600, and probably not finer than 320.

Gear

[barrabruce]

Thanks for the advice one and all.

I have tried to get "clover" brand compound but haven't had any success yet at any of the gun shops or other places I have tried.
Maybe looking in the wrong place.
Where else do they use it?? anyone.

I have valve grinding paste but I think its too course with no grit sizes labelled.

Does the sand paper for "wood" or wet and dry made of silicone carbide?? the grey stuff or the yellow stuff.

I have read recently burning some wet and dry and using the grit out of that is one source.Maybe mixing it with some grease etc for a compound.

Hmmm I think I can do this after some re-reading the posts and careful application.

Just need grit.



I will have to gather my bibs and bobs first and line all my ducks up in a row before I bravely go forth.

I have the powders and loads.

I have a 170 grns cast which is "just"engraves the nose section all the way back to the lube grooves and a PP mould with a long "just" bore dia core I wrap with so that's no hassle.
Brcue

[docone31]

You will find it in auto parts stores. It is a fairly common item.
Do not get the water based grit, get the grease based grit.
Go lightly, you can always fire a second time, rather than make the barrel smaller.
I fired 18 rounds, sized .0005 smaller than recquired, with the grit, it made thickness.
In other words, My Enfield calls for .314 paper patched castings, I went .3135 plus grit.
Made a shiney bore.

[barrabruce]

When I next go to town I will see if I can hunt some out at the auto stores.

That and when I can find a yellow tin of Johnstone floor wax I'll be set.

I'll light load some PP.
Rub some grit on the prodruding PP on a hard surface.
Wipe off excess
Check size.
Fire one or two and see how it looks and feels when cleaned up.

Go from there.

Till I get sorted I'll have to wait.

I will probably take some to the range and do some testing and maybe fire a few more if/when required after checking performance.

May be a few weeks thou before I can get out again.

Bruce

[geargnasher]

Keep in mind I was talking about firelapping with regular boolits, not PP slugs. You folks who treat your paper with abrasive are far advanced from whay I'm doing, and the grit may need to be finer.

Clover compound is usually available at REAL automotive stores (don't ask for it at Advance Auto unless you enjoy mentally torturing minimum-wage high-school dropouts). Most small engine shops and of course machine shops have it on hand.

Gear

[barrabruce]

Have having a sleep on it .
I think I will finish off the process with gearnashers way.
I can then concentrate on the chamber end and more to the front and feather it to the muzzle

That is one real nice way of doing it gearnasher.


Ohh yeah.... I get the look as if I have asked for a " bucket of steam" quite often.

[Zeek]

Here are some places to get your clover lapping compounds:
http://www.silver-seal.com/category/...elappingtools/

http://www.newmantools.com/clover.htm

The latter URL gives a phone number only for ordering.
Zeek

[barrabruce]

Well from local sources I found some
Hoults grinding paste fine.
I emailed them and got this reply.

Nothing on grit size but it is fine enough I think.
but...there is always seems to be a but.

Our grinding paste contains both silicon carbide and aluminium oxide in approximately equal amounts.

Isn't Alu carbide like diamond hardness??

I have burnt some 1500 grit wet and dry and used the ash on some PP with a few grains of bullseye.

Seemed to do something. I then wrapped a long patch on the cleaning rod and with auto sol metal polish gave it a bit of a rub.
It seems a bit less constricted in a couple of places. I may have ..one just cleaned the **** out of it...2. slightly done something.
The start of the barrel (bad bit) looks more uniform by a tad.

I found a tapered punch and used some "fine valve grinding paste" (relative term) and honed out the free bore end to the start of the rifling. It had a very steep jump up there and caused great troubles for me. I have attacked it once before but left a smigin
I have poured a lead cast of the chamber and from what I can gather from it the transition is now as one.
The free bore ..case neck sized portion jump down just now needs some attention but I will leave that till I have tested some rounds in it to see just how much damage I have done to it.



Now all you out there don't go all on me.
I have found some firelapping paste on the interweb down sth I can get.


I think I will get some of the finer stuff say 600 grit if this has had no effect.

Thanks for the help.
Stay tuned for a lot of wailing or celebration.

Barra

[barrabruce]

Errggghhhh.
Well while I was waiting for today to get to the range I decided that I would check out me gun and go the whole hog on it.
I found I have enough gap on the under-lug /hinge-pin to warrant shimming.
It was just wearing on the ends and not fully contacting the hinge pin on this break -open rifle.
So I ended up shimming it and now it is better than it was.(less flex and wobbles)
Maybe not as good as the experts may do thou.

The results can be seen here.
The highland factory 30-30 rounds were grouping a lot wilder than they are now so I have achieved something.
My PP experiments didn't greatly improve, but the plain low velocity seemed just as good as ever.

http://castboolits.gunloads.com/showthread.php?t=86386

conclusion.
I think I have achieved something positive.


I was getting build up after the 5 shot strings and think it was a mix of paper and fouling.

The end of the barrel is still black on the goove dia but the lands tips at least are clean looking.
Maybe gas cutting there.

Dunno but me PP boolits seemed to heat the barrel more the Jacketed rounds.

Should I get proper serious now and get to it with fire lapping???
Or maybe just cast a lead plug and do the hand route.

Happy with the results but a bit confused with the build up.
Maybe these dry only paches are too big or I need lube on then.
Any ideas there???.
Thanks
I'm still a long way from bowling pin necks thou.

Barra

[dubber123]

I have not done alot of paper patching, but when I did, I just put a drop of LEE Alox on the patched boolits just prior to sizing. It left a hard, waxy feel to the paper, and I noticed no buildup in the bore at all. In fact, I remember being surprised at how cleanly they shot.

FWIW, I have firelapped quite a few guns usuing the BRP instructions that Geargnasher posted, and couldn't be happier in each instance. It has always taken the 24+ rounds stated using the 320 grit compound. Good luck.

[303Guy]

Just out of interest, it would be great to see what difference wheat bran filler would make. I suspect that it would even clean out mild leading.

In a rough bore, I have noticed a difference when lightly lubing my patched boolits. The unlubed ones have more resistance in the push through sizer and sometimes they won't seat without damaging the patch. Lubed o patches seem to survive a higher powder charge in the bore.

Dunno but me PP boolits seemed to heat the barrel more the Jacketed rounds.

I've heard that being said. It could be due to something other than friction. I was using a load in my hornet that heated the barrel more than my 303. One day i accidently increased the charge a little and found the barrel stayed cool! The heating was even down the length of the barrel and included the suppressor, so it could not have been friction related. (I adopted that new charge as my standard - it was flatter shooting and harder hitting. That was for j-words).

[Canuck Bob]

Silicon Carbide lapping particles are available from Lee Valley Tools for mail order. A paste can be made at home. Also lapidermy shops stock the stuff.

http://www.leevalley.com/en/wood/pag...17&cat=1,43072

Also have an American website link.

[barrabruce]

I was just wondering!!!
How would auto sol metal polish or toothpaste go as an compound??
I know they are mildly abrasive.
After going at it with some auto sol metal polish on a rag for a bit I.
Tested it the range on the weekend after grinding the chamber free-bore area jump up shoulder hump to a more pleasing angle.
I think I got it concentric as well as the leade .

The PP didn't fare to good but I'm going back to some concoctions that group reasonably well before to re-test to see if there is any change in accuracy.

The factory and plain lubed cast bullets showed "more consistent and tighter groupings". @1 and less at 100yrds which is very pleasing.
(maybe a fluke..with my shaking and trigger jerking may have coincided with the bullets flight )

Fouling build up seemed even for what ever I used and easily cleaned. A tad more in the perceived tighter spots.

I am a bit "scared" to do to much more to it as its shooting so well.

YET

The bad area if you could see it now is something like well picture a new city road surface as a doo-gal-**** double air gauged match barrel.
Mine is a bit rougher than that.
Say well.

Picture a road grader on corrugated road after the wet season (all chewed up and corrigated..chatter marks) Started with.

Then I came along with a a grader did a cut over it or two and the road looks pretty smooth but needs a final cut to get its surface clean.
Smooth but has the ripples still in it. a few rounded over pot holes (galls and ripped land bits) and such but good.

Then I drove over it with my polish on a jag and although the ripples are still there it has smoothed them off a bit on the surface.



This is about where I'm at.
About the same point as where I started but different.




Hmm should I just drive down this road for a while to see if it gets better with my bullets??
Or try and cut under the surface and get rid of the bottom of the corrugation waves if possible and hope to get a clean rough surface to work with.

It aint too bad for a bush pig to say the least.

Would you.... leave it as it is now and enjoy it OR have a proper go at it???

Try a bit more PP first and " if it don't fly Wilbur" then go for it??

Procrastinating still
Not just to piss you off from good advice but cos I's worry to much.

Barra

[303Guy]

In my opinion? Leave it! It's working and with paper patching it will polish up and that'll be that. That metal polish stuff you mention sounds worth a try. Fine emery powder might be quicker to get it back to paper patch shooting smoothness. I'd say there are so many factors interfering with one hole groups that it probably is not the chamber, throat or bore anymore.

PS I wonder how many folks would have no idea what a dirt road or grader is?

[docone31]

I used to do paving.
I kinda have an idea.
I have run them also.