Hot glue for overshot cards for non fold crimp shells?

[Soundguy]

BPI makes Tyvek over shot wads that are very thin and similar to the house wrap used in construction. These seal all the good stuff under the crimp with no glue or wax or other stuff that can raise chamber pressure. These solve your problems.

KB

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Absolutely won't solve my problem with a round nose slug that contacts the roll crimp tool before the crimp is down far enough to hold the slug from moving front to back 1/8". I get the idea that there are many here not making their own non-flat nose slugs and roll crimping for them...

[Kennibear]

You can use an overshot card wad seated on the nose of the slug to hold it back under a roll crimp. It may disrupt the slug's flight but so will an uneven distribution of any sealant you use. Short of a sabot type wad made for the slug there is no optimal solution.

KB

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[longbow]

Depending on slug nose length and radius you may be able to modify your roll crimp tool by machining the center to clear the slug nose.

My homemade roll crimp tool has a concave center for that reason.

Longbow

[W.R.Buchanan]

Negative... It has to do with the nose of a slug and the roll crimp tool not being hollow.. The roll crimp tool hits the face of the slip before the edge is rolled enough to keep the slug from moving some...

That is because your Stack Height is too high or your hull is too short. Look at the pics on Post #13. You will see that the Slug was about 3/4" below the mouth of the hull before it was crimped resulting in a 3/8-7/16" long Crimp which landed on flat steps on the Slugs. Lee Slugs don't have that flat step and as a result are better served by Fold Crimping as discussed in Post #13.

I too have ran into the Roll Crimp Tool's center section hitting the nose of the slug. The solution is to use longer hulls or shorter wads.

Randy

[longbow]

3/8" to 7/16" is a very deep crimp Randy. Not saying it doesn't work as obviously it does but Tom Armbrust shows significant pressure increases for crimps as they get deeper. For instance:

- at 0.030" crimp depth the chamber pressure was 9,300 PSI
- at 0.050" crimp depth the chamber pressure was 10,500 PS
- at 0.070" crimp depth the chamber pressure was 11,900 PSI
- at 0.090" crimp depth the chamber pressure was 13,100 PSI

Not sure if that relationship of crimp depth to pressure continues but that is roughly 1200 PSi increase/0.020" of crimp depth.

I am sure the pressure is dependent on hull type and powder burn rate but 3/8" or more is a deep crimp by any standard.

The old Brenneke Classic slugs used to come with a plastic spacer that sat on the shoulder of the slug and came up flush with the nose so roll crimping didn't have to be deep. Not sure what they do now as I have not seen Brenneke slugs for loading in many years.

I try to keep my roll crimp depth less than 1/8" and closer to 1/16". Otherwise I fold crimp.

Longbow

[W.R.Buchanan]

Yeah, I don't think he is talking apples to apples? And I don't believe it applies to my loads as I would have already been blown up, since per that chart I would be looking at 4-5X the Chamber Pressure Increase which is like 50-60,000psi. I have no shotguns that could take 50,000 psi. Let alone the fact that the hulls couldn't take it either.

I get no Pressure Signs and no Increase in Recoil.

In the pics below the Slug with the Yellow Wad is a Factory Loaded Brenneke Slug. I bought a few boxes for HD when they were on sale. I Pity the Fool that gets hit by one of those!.

His Lee Slugs need to be done with a Fold Crimp anyway as there is no place for a Rolled Crimp to land on the slug. That's why all the Loading Manuals say Fold Crimp for both Lyman and Lee Slugs.

I have a bunch of Federal Blue Low Recoil Slug Hulls (Randy Mandrel?) that I used for my Reloads for Front Sight (Not supposed to use reloads at Front Sight but nobody could tell the difference with my loads) I tried doing a Roll Crimp on Lee Slugs in those hulls but ran into the crimp tool running into the nose of the slug. I started using the Brenneke lookin' Slugs with the Red Wad for those hulls. Same 18 gr. of Green Dot for about 1150-1200 fps.

I was able to get good Roll Crimps on the BPI AQ slugs mainly because the nose is a "Flatter Radius" than the Lee Slugs. It was close but the tool still cleared the nose of the slug. Compare the #3 pic with AQ Slug to the #4 pic with the Lee Slug and you can see what I'm talking about. The AQ Slug has a Flatter Nose Radius, which means that the crimp contacts the slug sooner. Also that slug is less likely to jam up the crimp as it exits than the Lee Slugs are.

Randy

[Soundguy]

Yes..lee slugs generally get fold crimped..thats why their slugs can fit some shot cups. I do like to save hulls with boogered mouths as well as load those new 2" shells...only way to do that is roll crimp.
I practiced my roll crimp today on some cut 2 3/4 and left the hulls longer and got satisfactory crimps that aren't excessively deep. Used some hand punched fiber wads to adjust slug height till it was good..also found a better lube for my roll crimp tool. All in all..the lee like folds.. But I do like the option to roll if I need to. Made up some today..no hot glue needed.

[longbow]

Randy:

I agree that if the pressure increases held up that apparent pressure would be very large with a 3/8"+ deep crimp. I suspect that at some point the pressure is enough to unroll even a deep crimp without adding more but at what point? Without pressure testing equipment it is pretty difficult to tell unless you get sticky extraction or noticeable increase in recoil.

It likely doesn't matter much if your loads are running 8000 PSI or thereabouts but if you are running 11,500 PSI then maybe. Plus I suspect that powder burn rate plays a part as well. A faster powder is building pressure fast while unrolling the crimp where a slower powder has a longer ramp up so isn't reaching peak pressure until after the crimp is open... maybe?

Since I have been through one blow up I tend to be pretty careful these days.

As for roll crimps and round nose slugs or round balls, I have roll crimped Lee slugs, 0.735" RB's and Lyman Foster slugs which are effectively the same as nose shape as a round ball. I was a bit reluctant about the 0.735" RB's but figured that if factory Fosters and other round nose slugs can be roll crimped then so can a 0.735" RB and so they can without any issues at all. In my experience anyway. I figured a Lee slug in a shotcup wouldn't work well roll crimped but saw that others had done it so tried it and surprisingly to me it worked and the roll crimp didn't affect the wad petals which is what I thought would happen. Recovered wads looked fine.

I like to roll crimp slugs for two main reasons: 1) I can accomodate different column heights and the hull length down't matter much if trimmed short and a shorter wad column is used... except the jump from chamber to forcing cone is longer; 2) I can easily see that a slug is loaded in that hull.

Different strokes.

Longbow