Die dimensions for home made dies.

[Casper_SWAT]

Anyone have or know where I can find dimensions for the rebate die angle? Im also debating on making a bullet size die to size .311 bullets to .308 so I can swage 2 bullets with one die set. What yaw experienced swagers think?

[Valornor]

Typical boat angle can range from 6 to 8 degrees per side. I typicall go middle of the road with a 7 degree boat tail.

I have the opposite problem as you. I am swimming in 155gr OTMBT .308 cal and have been considering sizing up to .311 cal....or at the very least adding dies to my .308 set to make .311 cal bullete.

Drawing a bullet down in diameter isn't always a good idea as it tends to have a detrimental affect on accuracy...

[Tatume]

Drawing a bullet down in diameter isn't always a good idea as it tends to have a detrimental effect on accuracy...

This statement does not coincide with my experience.

[Valornor]

I've had mixed results. I do it all the time with cast bullets. With jackets bullets, I've had mixed results.

[Casper_SWAT]

Ok, so I may need to just make an additional bullet point die and size a .311 to .308 then run it through a .308 pointing die also.

[Casper_SWAT]

And sence this thread is supposed to be about die dimensions what is the ID of a pointing die? I would supposed you would have to compensate for spring back and make the die a few ten's above the target diameter.

what would the common diameter of a .311/.308 lead swage die be?

[clodhopper]

I have never made a swage die. But the springback of a lead core bullet is going to be pretty small.
I think most die makers polish, then make a bullet and measure the bullet to determine if the die is the right size.

[aaronraad]

The bullet swaging die makers usually talk about a 0.006" reduction as maximum in bullet diameter. I can't help but feel this number reduces as you go smaller in caliber.

I currently have 2 bullet reducing dies in a smaller caliber. Both dies are for a specific projectile and there is no guarantee the diameter will reduce correctly for another projectile, possibly not even for a different batch. The bullet reducing dies are therefore polished to order.

Interestingly one bullet reducing die pushes the original diameter projectile through base-first, while the other projectile pushes meplat-first. Both dies cause a reduction in bullet concentricity when compared over the Vern Juenke Machine. Concentricity seems to be restored though after both bullets are pushed into the point form die 3x @ approximately 120 degree offsets. To be proven on paper yet.

If I had the room to move with the 0.006" maximum reduction going from 0.3110" to 0.3080": I would reduce to 0.3075" to 0.3070"; and then swage up as per normal to 0.3080" to maximize concentricity. If the concentricity error of the original projectile though is in the jacket, you are never going to improve on the original tolerances/variations.

Just be aware that not all 0.311" projectiles are the same, variations in spring-back will vary the final diameter. I would also be wary of the jacket and core material(s) hardness, especially those with a steel core. FMJ's with exposed lead bases might also behave radically different to open tip designs, you might need a very good punch to die fit to avoid bleed-by for high pressure bullet reductions. 144gr FMJ ADI 762NATO projectiles were commonly re-sized to ensure consistency in Australia during the 80's when they were the only approved projectile for TR fullbore matches. The reduction was only by 0.0010 to 0.0020" and there was no steel core...this led to the onset of tight groove match barrels down to 0.3065". Unmonitored, over-polished or worn bullet reducing dies led to massive pressure (velocity) rises and a few banana-split barrels and/or set-back locking lugs.

[Casper_SWAT]

I just purchased an RCE walnut hill press and I'm currently working on a set of dies. I am almost finished with the cupping and draw dies, I just have to work out some dimensions. So, I wonder If I were to swage a .308 bullet then swage up to .311? My goal is to fabricate the least amount of dies necessary to swage, .311 and .308. Still working on the dimensions needed to complete all the dies.

[Casper_SWAT]

I need input on punch length for the RCE walnut hill. The best I can assume is the base for the bottom punch should be 2", and the length of the punch should be the same as the die? I am making the bottom punch separate from the base, with a set screw in the base locking the punch, so I can replace the punch if it ever breaks/chips.

[aaronraad]

I need input on punch length for the RCE walnut hill. The best I can assume is the base for the bottom punch should be 2", and the length of the punch should be the same as the die? I am making the bottom punch separate from the base, with a set screw in the base locking the punch, so I can replace the punch if it ever breaks/chips.

You could always dummy up a punch with a piece of dowel to get the optimum length to match the press force and displacement curves.

If you are still considering a bullet reducing die, how are you guiding/aligning the projectile on the punch before you go into the reducing section of the die?

You might also need to take a similar punch alignment approach when pointing up .308 to .311 in the point form die; as that's more waggle room than you'd expect compared to coming from a .311 core seater die. Systems like the Whidden bullet tipping die don't use core seater-to-point form die clearances. They are designed to only fineness the meplat softly. When used incorrectly with too much pressure, ogives deform and concentricity deteriorates as they are largely unsupported in the bullet tipping die. Just something else to keep in the back of your mind if things go pear shaped.

[Casper_SWAT]

That kinda what i was thinking with reguards to sizin my punch, just have to make long shafts and take them home and measure.

I think at this moment i have decided againt a reducing dir due to concentricity concerns.

I have already completed a tipping die just like the whitiden pointing die with one of their pointing inserts, my die cradles the bullet and floats the pointing insert.

Here is a pic of my tipping die.

[aaronraad]

That kinda what i was thinking with reguards to sizin my punch, just have to make long shafts and take them home and measure.

I think at this moment i have decided againt a reducing dir due to concentricity concerns.

I have already completed a tipping die just like the whitiden pointing die with one of their pointing inserts, my die cradles the bullet and floats the pointing insert.

Here is a pic of my tipping die.

Nice work!

I assume there was a lot of good learning there in replicating a commercial system that works?

This should definitely give you confidence to machine your own punch & die designs.

[Casper_SWAT]

I don't really lack the confidence to do the machining, being that im a machinist. I just like having the dimensions before hand. I don't really like doing things over, but I guess thats the way you learn and develope better skills. Thought that by asking some questions, someone would give up some dimensions that would help with jacket draw dies so I can make jackets for .308 and .311 bullets without waisting time.

[aaronraad]

I don't really lack the confidence to do the machining, being that im a machinist. I just like having the dimensions before hand. I don't really like doing things over, but I guess thats the way you learn and develope better skills. Thought that by asking some questions, someone would give up some dimensions that would help with jacket draw dies so I can make jackets for .308 and .311 bullets without waisting time.

The more you learn (including the questions you ask), the more you realize that there are too many parameters you can't control enough that affect the end result if you don't make punch & die adjustments long the way. It's one of the reasons RCBS got out bullet swaging dies decades ago and just stuck with reloading dies.

Have you read Ammunition Making by George E. Frost? There is some absolute gold in the book. The Biehler & Astles Dies (B&A Dies) swaging and ordering brochure is also useful in helping to understand some of the swaging vs drawing relationships.

Berger Bullets wouldn't exist if they didn't merge with J4 Precision (Spiveco) decades ago. Not just for the the precision jacket supply, but because they came with a tool room and the deep drawing tool makers to boot. Berger just could not source their dies to the tolerances they require from external suppliers.

[just bill]

I had a curiosity about the bullet diameter swaging so I went back and re-read Corbin's reducing die information and he has a lot of words to say things about his BRD dies, but nothing really positive. It can be done but he even says something simular to the fact that even the doner bullets you have send to use to make the die can differ within themselves as well accuracy/consistency by diameters can be not to accurate. He even says he can't guarantee the dies performance due to material reactions and spring back and the like, as I interpret what he writes.
Bill

[Casper_SWAT]

I did the same and have decided against it. Was attempting to kill two birds with one stone but seems like thats more trouble than just making the nessesary dies.

[Casper_SWAT]

Thanks for the info one the book, ill look it up.

[seppos]

Just make two pointing dies for .308 and lap the second one for . 311. You could use the .308 punch if you are making open tipped bullets. The jacket wall is thick enough to support the base even if the punch is undersized. When you make bullets make them . 308 and those used in .311 are just bumped up in .311 bump die. So basicly you only need the core and seat die for .308 and point dies for both .308 and .311.

S

Ps. When you make the first, lap it to .308 and make a test bullet. Measure it and if it is over .308 put down the info about the diameter. You could use that when opening up it to . 311. Make it undersized according to the previous info ( test try with .308).
Use the same info when you make .308. After the first try you will know, how much undersize the diameter should be to compensate the spring back.

[Casper_SWAT]

Just make two pointing dies for .308 and lap the second one for . 311. You could use the .308 punch if you are making open tipped bullets. The jacket wall is thick enough to support the base even if the punch is undersized. When you make bullets make them . 308 and those used in .311 are just bumped up in .311 bump die. So basicly you only need the core and seat die for .308 and point dies for both .308 and .311.

S

Ps. When you make the first, lap it to .308 and make a test bullet. Measure it and if it is over .308 put down the info about the diameter. You could use that when opening up it to . 311. Make it undersized according to the previous info ( test try with .308).
Use the same info when you make .308. After the first try you will know, how much undersize the diameter should be to compensate the spring back.

This is what i decided to do, thanks. I have not started on the bullet dies yet as I'm still working out the details on my jacket forming dies.