sticky swage punch

[YR!]

I have a standard set of swaging dies for 6mm/243. I love the results but have a problem with the core seat and BT form dies. the jacketed cores stick on the punch and I have great difficulty getting them off. I ding the rims and make defective points. Does anyone have a solution to this problems?

Mark

[JonB_in_Glencoe]

Is the punch lubed?

[Zbench]

And who made the dies?

Seems to me that you are not fully expanding the jacket in the core seat die. If you did, the jacket would grip the die walls more tightly than the core seat punch. This is typically due to using the wrong sized core seat punch. If it's too small, lead gets past the punch and doesn't develop enough pressure to expand the jacket. If it's too big, you are jamming the die into the copper and deforming it as you seat making it much harder to pull off. The punch really has to be "just right" A difference of .001" is sometimes enough to make a big difference.

You can pretty easily calculate what size punch you should use. Measure the diameter of a lead slug with no jacket with an accurate micrometer. Let's say it measures .242500 which is not unreasonable for your caliber. You now know the inside diameter of you core seat die. You will of course need a standard lead tip seat punch to do this.

Now look at a jacket you have seated and take a tubing micrometer and measure the jacket thickness of one that has not been seated. Measure at the same point that the core is seated on the example. Try to find a jacket that is as perfectly concentric as you can. Let's say you find that perfect jacket and you measure the jacket thickness in the area you are seating is .01263" Multiply this by 2 and you get .02526". Now, take that and subtract from the inside die diamter = .242500-.02526 = .21724"

That is the ideal size of your punch. Most makers can deliver a punch at 1/2 thousandth accuracy. I would request one at .217 which is just slightly undersized but will likely be perfect.

That's how you size a punch. If your jackets are tapered, you will need a different punch for a different weighted bullet as at a different spot inside the jacket it will be a different thickness.

Hope this helps.

[BT Sniper]

What are you using for a jacket? 22 mag brass or commercial jackets?

[BT Sniper]

Are those "BT" boat tail dies or BTSniper dies? I assumed they where mine but reading a bit closer might not be...

The core seat punch is machined to fit the id. of the specific jacket to be used. Might be using wrong jacket or wrong diameter punch.

One thing to try... carefully.... apply less lube to the jacet and apply just a little more pressure when seating cores so jacket swells out and stays in die rather then stuck on punch. Also try just a little lube on tipoff punch too if you like.

If none of this works sounds like you would need a jacket with a thinner wall or smaller diameter punch.

BT

[YR!]

Commercial jackets from corbin. dies from corbin. swaging press from corbin.

[YR!]

Boat tail. from corbin.

[Time Killer]

I have had that happen for reasons not mentioned above. Some core seat dies are attuned to a certain weight range for your cores. If you are crushing the top of the jacket you do not have enough core material in the jacket for proper expansion in the seater die, or your jacket could be a little to long for your desired weight range. This will not allow for proper expansion of the jacket and will also produce bullets that are not the correct size. Some of the jacket will reach the right diameter and some of it may not. It only takes being off a little bit at the bottom of the weight range with the core for jacket size to cause this issue. Increase the weight of the core until you no longer crush the rim of the jacket with the seater die. As mentioned before also a little lube rubbed on the seat die every 3rd or 4th seating will help with the release from the lead. A way to check your core seater for this issue is to see if it is straight walled or it has a step at the end of it. the ones with the step can cause this issue. Based on your description of what was happening it appears to be a stepped die or it is hitting some type of rim to crush the top of the jacket. Best I can think of right now without pictures. #9 bird shot are approximately 1 grain each and work well for checking this issue.

[Zbench]

YR,

This issue is easy to fix since you are dealing with Corbin. Just sent him a sample of your jackets, your seated result and your die and punch and he will recommend what you need to do. I'm sure it's getting a proper punch. He doesn't charge for this service, you will just pay for the punch. If you are using his jackets, they are tapered and are impacted by core height as defined above. You might call first to discuss with him so he knows what the issue is. They will give you a solution that works. Turn around is very fast, maybe only 10 days if you send priority mail.

[YR!]

The core seat punch delivered with my Corbin die set is marked .2225. When I seat my cores, the punch expands the jacket and the springback grips the punch tighter than the die body friction. It pulls the jacketed core out of the die on the punch.

[BT Sniper]

Might be time to contact Corbin.

Did you try less lube on jacket, more on punch and apply a little more pressure?

[garandsrus]

You probably need a punch that is .001 or .002 smaller than what you currently have. The jacket you are using might be a little thicker than the punch you are using is designed for. No big deal.

[GONRA]

May or may NOT be useful here - but GONRA made a stripper for my Corbin CSP-2 press that takes care of all sorts of goofy
"sticking to the punch" issues THAT CAN DRIVE YOU NUTS. (Hint: Be careful when you GOOGLE "stripper".)