Can I cut a bullet to meet my OAL?

[Kev18]

Long story short: I have an old 1886 winchester in 40-82. It has a slow twist. I cast my own 260gr flat nose boolits and they work great. Now I want something heavier. My only option in commercially made ammo is a 40-70 bullet. These had faster twist to stabilize the long heavy round. These are over an inch long, i would need about an 0.9 OAL if possible.

Could I cut a grease groove off somehow? Will it affect anything?

And If I try to load a full round for fun, will it affect the pressure in the case. Il knock a few grains off my load of course.

What I want:
http://www.thebulletbarn.com/images/NewBullets/Rifle/17-40-70-RNFP-FB-370gr-lg.jpg

Close to what Im shooting:
http://www.thebulletbarn.com/images/NewBullets/Rifle/12-40-65-RNFP-BB-DLG-260gr-lg.jpg

[earlmck]

Certainly you can cut them shorter. I have done similar: I like to load them first so I have the whole cartridge to handle, build a "stop" for length and saw them off in the power miter saw. That means you are cutting off the tip rather than a grease groove and that would be my first guess as to the best way to shorten up that nice looking boolit.

[Walks]

I have one too.
Use Lyman #403168-200gr, 403169-240gr & RCBS 260gr. The Lyman 240gr shoots best. I think the twist is too fast for a bullet heavier then 260gr in that rifle.

[Kev18]

I have one too.
Use Lyman #403168-200gr, 403169-240gr & RCBS 260gr. The Lyman 240gr shoots best. I think the twist is too fast for a bullet heavier then 260gr in that rifle.

I have pretty much every article ever on the 40-82, from the 60's till now. From what Iv'e seen, a 330grain is the heaviest anyone has ever shot with good accuracy. People have shot heavier just not with decent accuracy.

[Kev18]

Certainly you can cut them shorter. I have done similar: I like to load them first so I have the whole cartridge to handle, build a "stop" for length and saw them off in the power miter saw. That means you are cutting off the tip rather than a grease groove and that would be my first guess as to the best way to shorten up that nice looking boolit.

I dont have a small miter saw or anything.... I have a big one. Does cutting grease grooves do any damage to the bullet? I would think slicing off the tip would affect accuracy?

[reddog81]

defects on the base effect accuracy much more than defects on the tip. Defects on the base upset the bullet as it's leaving the bore and throw the bullet out of whack. Defects on the tip don't have the same effect.

[Kev18]

defects on the base effect accuracy much more than defects on the tip. Defects on the base upset the bullet as it's leaving the bore and throw the bullet out of whack. Defects on the tip don't have the same effect.

Alright, thanks! makes sense.

[garandsrus]

If it’s a permanent change, you can have the mold shortened to cast whatever weight you want. Cutting off one grease groove is probably the most common.

[44Blam]

I wouldn't cut a boolit... Seems like it would do a lot of bad things. One would be expose you to lead dust and another would be suspect accuracy...
It's probably better to seat it deeper or get a different mold.

[country gent]

A simple collet mod would allow a trimmer to be used to trim down either end of the bullet before loading. A drill press and set of wood blocks could also be used done right with the right cutter you could possibly do 2 bullets at a time here. One on each side of the cutter. Lead is a little different to machine as its gummy and soft. But this is has been done before.
Modifying the trimmer collet:
Measure the cuts that allow the collet to collapse width. shim all to this and insert shims into gaps tighten collet in holder.
set up square and true in lathe or drill press and drill collet out close to size of bullet. on a .410 dia I would shoot for .400-.405 this leaves .005-.010 to polish to dead nuts size.
leave a shoulder for the base to set against at depth. to trim base a small washer disk inserted provides a stop for the nose. Here I would cut the new size as deep as the bullets bearing surface for the best alignment. The trimmers cutter is center cutting and should do fine for this.

Drill Press fixture.
With 2 blocks of hard wood, install 2 pins press fit one side sliding other. This makes your clamp.
lay out and drill 2 holes 3/4" apart on center between the 2 blocks drill this hole 1/4" larger than bullet. and to depth plus 1/8"
Use epoxy (JB weld) or bedding material to make the holes to size using the bullets coated with release agent to size.
re split blocks as needed after epoxy cures.
This lock can now be set in a bolted down vise and a flat cutter used to trim down the bullet.

Another option is to do a few my hand with a file and test If they work send to One to accurate or one of the custom guys and have the mould made. then cast what you want

[waksupi]

Is your bullet already set out as far as it can go in the chamber? If not, that gives you some room to use a longer bullet. Keep in mind, when you go to a heavier bullet, the powder charge does decrease, and may make up in less case capacity for the added projectile length. I would use a powder charge to the base of the bullet loaded to the length you can manage, and see how it performs.

[country gent]

If you can find the mould for #1 pic it could be modified to an adjustable nose insert allowing for fine tuning.
This would require some precision machining

Set the blocks up and indicate to true.
drill nose thru blocks and bore to size.
Turn nose insert on 5/16 24 threaded stem
Set blocks up in mill and rill and tap 2 10-32 holes on each side of nose hole.
machine a flat plate 1/8" x 3/4" x width of blocks 2 slots one each end 5/16 24 hole drilled and tapped center.
with 2 shoulder bolts attach the plate to the blocks and insert the nose plug in with a jam nut on the threads. set to desired weight length and cast.

[Kev18]

I dont have the mold for the bullet I want. Il buy a bag of 200 of them,.

[Kev18]

I checked and it would be 83$ + taxes+ shipping. Which would probably be 100 something CDN for 200 bullets.

But I went on accurate molds and I could get a 40-82 mold 300 grain, .406 dia ...etc Pretty much what i want for 99$ US Which is about 134$CDN... So im wondering if il just get a mold even if the wait time is 3 weeks.

[JBinMN]

I checked and it would be 83$ + taxes+ shipping. Which would probably be 100 something CDN for 200 bullets.

But I went on accurate molds and I could get a 40-82 mold 300 grain, .406 dia ...etc Pretty much what i want for 99$ US Which is about 134$CDN... So im wondering if il just get a mold even if the wait time is 3 weeks.

Get the mold.
;)

Boolits go away, or be trapped & remelted anyway. The mold allows for continued use & you can make "wayyy" more than 200 boolits with it for the extra +/-40 frogskins.
;)

You can always resell the mold later. The boolits on the other hand, are basically history after they are shot & ya need to buy more if ya want more...
;)

Suit yourself though. Just buying the mold, was just what "I" would do.

[Kev18]

Get the mold.
;)

Boolits go away, or be trapped & remelted anyway. The mold allows for continued use & you can make "wayyy" more than 200 boolits with it for the extra +/-40 frogskins.
;)

You can always resell the mold later. The boolits on the other hand, are basically history after they are shot & ya need to buy more if ya want more...
;)

Suit yourself though. Just buying the mold, was just what "I" would do.

I think you are right. Its worth it. I now cast my 260gr with an original Ideal reloading tool. Never had any issues with a solid mold.

[45-70 Chevroner]

This is in no way a criticism. You a are defeating the perpose of a heavier bullet, you buy a heavey boolit and then cut it off that's a lot of work, why not just find a mold that will be just long enough to seat out to the lands and groves. A 260 gr boolit is a pretty hefty boolit for that gun anyway.

[JBinMN]

This is in no way a criticism. You a are defeating the perpose of a heavier bullet, you buy a heavey boolit and then cut it off that's a lot of work, why not just find a mold that will be just long enough to seat out to the lands and groves. A 260 gr boolit is a pretty hefty boolit for that gun anyway.

Good point, and at least "I" agree with that option, but it was not proposed before, if I read things right. IMO, It is certainly worth Kev18s consideration & good that you mentioned it for him.
:)

I think that either way, buying a mold, one as mentioned or another, will likely turn out better than buying the boolits at the prices proposed earlier.

The only advantage I can see right now with Kev18 buying the mold he was talking about, is that if Kev18 wants to use that boolit in its original boolit size some time in the future in a different firearm, he would then have that mold & perhaps use it for both.

IMO, it is still better than buying just the boolits all of the time & then cutting them down, as per the cost comparison between buying boolits & buying a mold to make more boolits...

Making sure that that size /weight boolit will work in the firearm he wishes to test, is the first job to do, and apparently the cost of buying a mold that can be re-sold, is a better use of funds than just buying the boolits alone, to do the test, due to the possible return on the mold if the boolits from it do not work, while the cost of the boolits alone are not comparable in the end.

While he may sell/trade the mold(any one he might choose) and recover much of his "testing" expense, the sell/trade of the boolits may not be so easy/worthwhile to recoup their cost(s) like shipping, etc..

It is certainly something for Kev18 to consider, and again, it is another worthwhile option to consider & was well worth mentioning!
:)

[AllanD]

Actually I would think about lathe turning the top off of a crimper/seater die
and using a saw/file to shorten the bullet while firmly in the die.

[Kev18]

I think il just get the mold... Il order it soon. Everyone is saying that the whole bullet thing is dumb. And I agree. Maybe if they would be really cheap, but they are not! Mold is better in the long run anyways.

[JBinMN]

I think il just get the mold... Il order it soon. Everyone is saying that the whole bullet thing is dumb. And I agree. Maybe if they would be really cheap, but they are not! Mold is better in the long run anyways.

Good to hear. Let us know how things work out later, when you go to testing things out.
:)