Opening up a Mold, 1-2 Thousands

[cigg52]

I have been looking at the RCBS 41-300-FN mold for a hunting bullet for my Sharps rifle. The thing is they list it as .406 dia. and I need a .408 bullet.

If I get this mold what would be the best way to open it up 1-2 thousands? I have a cordless drill and a drill press. I will probably be casting it at 20-1
Thanks

[Elkins45]

I have been looking at the RCBS 41-300-FN mold for a hunting bullet for my Sharps rifle. The thing is they list it as .406 dia. and I need a .408 bullet.

If I get this mold what would be the best way to open it up 1-2 thousands? I have a cordless drill and a drill press. I will probably be casting it at 20-1
Thanks

Search this site for the term leementing. Do the leementing procedure with valve grinding compound instead of Comet. That's how I would do it...just be very sure to keep the compound off the shank if it's a gas check bullet. The last thing you want to do is make the base too big for a check to fit.

[scb]

This the sort of thing your looking for?
http://www.hollowpointmold.com/band-modifications/?picture=589#589
From what I can see his prices for this work seem very reasonable to me. A lot cheaper then ruining a new mould.

[longbow]

0.001" to 0.002" can be lapped out quite easily.

The process is similar to Leementing as mentioned but more aggressive. Take a look here:

http://www.castpics.net/ under "mould references" then "mould lapping"

It will take a bit of work with an iron mould but if you take it slow, open and clean the mould often to keep grit from building up between the mould faces you can easily take out a couple thou.

I have lapped some moulds out by 0.003" and gotten very good results.

Something even easier and maybe suitable here is to try "Beagling". Do a search on Beagling.

Basically it is a simple process of shimming the mould blocks apart to get a larger diameter boolit. It can work very well, is easy and doesn't permanently alter your mould.

Longbow

[JJC]

Definately check out the stie SCB noted. Some of my rcbs molds cast larger than spec by .2 you may be good to go if you can spare the money and measure some?

[MtGun44]

Beagle it first and see how it works without doing anything permanent. If you like it,
lap it out.

Search on "beagling" and "lapping mold".

Bill

[northmn]

I have "beagled" a couple of 30 cal molds for a 303 and 7.62 Russian. I have used the aluminum duck with good results. A couple of strips along side the bullet cavity. Works bettr than it sounds and would save you some effort as compared to lapping.

DP

[Bullshop]

Does not beagling produce an oval shaped boolit? It can only increase diameter of measured opposite the seem line by this method. The seem line will still be the same diameter, correct? If then the boolit is sized to the larger diameter there will be a void on opposing sides, yes? If sized to the smaller diameter there will be uneven sizing and noticeable distortion to the drive bands on the increased diameter sides.
I just fail to see how this deliberate introduction of imbalance can help to improve accuracy.
Personally I would prefer to stay with a round boolit even if it is undersized. I would then develop a load for said boolit cast of a suitably soft alloy and work with a suitably fast powder that will produce enough upset (obturation) to seal the gas and fill the grooves adequately to deliver enough spin to the boolit.
This is exactly what is being done with modern ML shooting slip fit conicals powered by fast smokeless (BP substitutes) powders.
Sorry for going against the grain on the beagling thingy as I know many here do it but for me its like scratching your fingernails on a black board, it just make my hair stand up.

[35remington]

Well, the bullet is still balanced as the two sides are still symmetrical. Large side is opposite large side; small side is still opposite small side. No less an authority than Veral Smith notes this is true.

It's free and worth a try. If no go, then lap it.

I've used beagling to make supposed bore riding bullets actually bore ride, and in many cases it helped.

[Bullshop]

If a bore rider design has too small a diameter on the bore ride nose and it is beagled to ride the lands cant that boolit still bend or slump to either side that does not fit?

[35remington]

I suppose theoretically, but the thing is the enlarged bullet shot a lot better than the nonbeagled bullet in my Microgroove Marlin, halving group sizes. One of several examples where better results were obtained. This particular one was from a group buy here that did not have the bore riding diameter it should have (a .360 225 grain in a six cavity Lee). Beagling it helped in both Microgroove barrels and in my 350 Remington magnum and a 357 Maximum barrel.

Since the nose is supported on two sides and isn't subject to pressure like the base is, things may be working out in terms of fit such that it makes good shooting possible, and possibly slumping wasn't an issue because it seemed to shoot.

Anyway, fit on two sides is better than having no fit all around the nose of the bullet. At least the rifles thought so. It's possible that having the rifling filled all around the rear bands and two sides of the nose to bear the front end might be enough.

It was an attempt at fixing the problem that cost me nothing, and I also had nothing to lose anyway. Free is always worth a try. Whether it will help everyone is something I cannot say.

[Bullshop]

I understand what your saying and agree that two sides would be better than one.
Still I have a problem with the idea of beagling. It just dont mix for me like oil and water.
My mind just refuses to accept it as a cure. No big deal its just the way my mind works.
Minds are kinda weird that way. Like for instance my son will eat peas and he will eat potatoes as long as they are separated on his plate. If they mix he wont eat them. Something in his mind tells him it ain't right. I have found that such things are quite common with people.
In this case my mind tells me beagling ain't right and I cant get past that. I am reading how so many people do it and seems to work for them but still when I consider it I still get the fingernails across the black board feeling with the hairs on the back of my neck sticking up. I JUST CANT DO IT!

[MtGun44]

Regardless of how you THINK it might work, lots of folks have had excellent results.

I suggest you try it rather than giving yourself a headache coming up with reasons
that it can't work. Seems pretty odd to me, too, but with so many successes, I just
figure it doesn't work the way I think it would. Wouldn't be the first thing I didn't
understand how it worked.

I was always worried that it would leak out and make fins, but apparently it doesn't.

Bill

[cigg52]

Thank for the good advise guys. If I get that mold I will definitely cast some up first, and see what I end up with. Thanks again.

[nanuk]

Bullshop, perhaps you need to try it and measure the casting.

then you will actually know how it affects diameters compared to non beagled castings.

I understand your issues, as I thought the same.

I have never tried it, but when I get my setup going I will just to see what it does.

Hey, it is free, does not damage the mould, and is reversible.

Worth a try? Just like pouring water in a carburator to de carbon cylinder heads! "They" say it works!

[Bullshop]

Nothing is free! There is a cost in time. And like MtGun44 said it will prolly just leak out through the gap between the blocks. I would have to add some zink to the alloy to make it less fluid. According to another thread I can just burn the tin out so that should help too. NOT!!!!
Just how would it look to my customers when they measure the boolits they get from me? Maybe I need counseling or something. Is there an " I cant beagle " support group or something like that? Maybe I only look normal but really desperately need help.
OK yall know I am only pulling chains right? Its been cold (-20 to -50) for three weeks and I am getting kinda gitty. They are saying 20 above next week, WOO HOO!!!
That may get yall some relief from me.

[longbow]

Well Bullshop, I have Beagled a mould about 0.003" and it worked fine. The seam was bigger but no "flashing" or fins and, the boolits shot better because they fit the bore better.

It isn't fancy or flashy (hah! no pun intended) but within limits it does work or it did for me. In the end I lapped the mould out. The oval boolits bothered me even though they shot well.

So, I understand your objection to oval boolits. However, since the gun didn't care, why did I take so much time and effort to lap out the mould? The only logical reason I can give is that I wanted a permanent fix and I didn't have any use for the smaller boolit. So I spent hours lapping the mould instead of minutes applying tape that "might" come off some day and take minutes to repair.

Makes me feel silly.

Longbow

[NHlever]

Nothing is free! There is a cost in time. And like MtGun44 said it will prolly just leak out through the gap between the blocks. I would have to add some zink to the alloy to make it less fluid. According to another thread I can just burn the tin out so that should help too. NOT!!!!
Just how would it look to my customers when they measure the boolits they get from me? Maybe I need counseling or something. Is there an " I cant beagle " support group or something like that? Maybe I only look normal but really desperately need help.
OK yall know I am only pulling chains right? Its been cold (-20 to -50) for three weeks and I am getting kinda gitty. They are saying 20 above next week, WOO HOO!!!
That may get yall some relief from me.

I'm on your side on this one Bullshop. There is nothing wrong with trying it, and I guess it works in some situations, but I would have to be a bit desperate to do it in my molds because it seems like such a band aid. Heat, and adhesives seldom mix well for long, and the whole idea of it just doesn't seem the thing to do for me either. Many things that "work" sort of usually have a better alternative solution.

[Bullshop]

NHLever
Your my new best friend!

[BABore]

Bullshop,

My take on Beagling is this. A guy gets an undersized mold and the boolits don't shoot worth beans. He Beagles the mold, gets an egg shaped boolit, but now can shoot some beans. Some beans is better than no beans so he's happy-happy. Maybe one day the guy gets a mold that drops a correct size boolit that actually fits has rifle. Then he can shoot all the beans.

[451whitworth]

i once bought a mould for a 348 WCF that dropped bullets at .350". they shot foot patterns at 40 yards out of one of my model 71 rifles. so i used some Renolds wrap to space the blocks open to get the bullets to drop at .352" and tried them. bingo, i had groups not patterns anymore. they were bigger in diameter one direction vs. the other but it did allow me to figure out what diameter mould i need to have made up.

[Dan Cash]

For what it is worth, I have noticed that most of my Lyman moulds are wider across the seam than 90 degrees to the seam. Some of them shoot really well. Perhaps Beageling will make the cast more round in the long run?