[capvan]

I'm using a MEC 9000 progressive machine. Using AA hulls. About 1 in 50 shells ends up with a crimp that won't stay closed. It isn't apparent immediately, but happens over a couple of days. I don't see it when I'm putting the shells in the box, but a couple of days later I notice a "bulgy" spot in the box and find a shell that has a open, or partially open crimp. I hate to make any adjustments on the machine since it has been behaving particularly well for a few months. Any ideas?

 

[Guest]

Wat too many varibles to call this one.

Which hull, new style or old?

What load are using when this happens?

How many times have the hulls been loaded?

How much wad pressure?

These will all directly affect the problem you descibed.

ec90t

 

[RSVP410]

Some thoughts. It sounds like your component selection might be overfilling the hull and then your crimp is not deep enough and or the wad is being compressed too much and relaxes back to it's original length over time. Might try a different wad, I've had best luck using a Remington figure 8 in the Winchester AA 2 piece hulls.

Another issue is that as hulls age, the plastic in the crimp area gets thin, split and brittle and does not hold a crimp as well.

Scott

 

[capvan]

Old style AA hull. 16.8 gr. of Clays, 1 oz. load. XL wad. I have no way of telling how many times the hull has been loaded. I don't keep track, just discard when there are any split lines. No wad pressure. I have always been told that this is unneccessary with the plastic wads. And remember, this is one out of 50-75 hulls. All the others are just fine.
Bruce

 

[capvan]

t

 

[TjayE]

Your final crimp is not deep enough. Set the final crimp to .060" depth and your shells will not open. Some of the new powder recipes are calling for as much as .090" crimp depth.

 

[blkfin]

Capvan, using my hornady 366 some crimps start to bulge after about 5 reloads using the same data. After reloading 4 times I use the hulls for practice only. I tried adjusting the crimps, had the same results. Mike K.

 

[TC]

Bruce, you really can't do much about it. Eventually the plastic weakens from being folded so sharply in the same spot. Holding the handle down for a couple seconds will "set" the crimp a little better but won't completely eliminate it. Tony

 

[shot410ga]

This is one of the reasons why I went to a Dillon reloader. I had the same problems with Mec. Never had the problem with a Dillon, it's easy to adjust.

 

[Hap MecTweaks]

shot410ga, I'd hafta guess your fine Dillon loader's final crimp depth is close to a factory shell too.

The 9000 series Mec's are easy enough to get that same crimp depth too.

Hap

 

[Neil Winston]

capven, though your wad-pressure - at that stage - could well be zero, your crimp is adding it later.

As RSVP410 says, it's just a component mismatch. A less bulky powder - or whatever will lead you to be able to use a smaller volume of powder - or shorter wad will fix it (and nothing else will.)

Neil

 

[Doc!]

capvan - I use a winchester orange wad with that exact load - works great. I have opened my bar to drop very close to a real ounce of the shot I use

 

[Shady Creek]

You just need to tweak that old Mec a little. You "do" want the crimp depth to be equal to a new shell,if not,you will have a problem. What is your wad pressure,size hole after starter crimp,is your crimp depth enough????? It takes a little time but it will be worth it and go slow. Everyone will tell you,not to use wad pressure(I use 40psi),I don't get squib loads,I've got a good crimp,works for me. If I could just hit them all,life would be better. GOOD LUCK

 

[Neil Winston]

Shady Creek, you have to keep in mind that though you use 40 pounds, if the powder/wad/shot column is shorter than the inside of the shell, the wad can relax to pressure=zero and the crimp is not going to open up.

Neil

 

[dr.beav]

You probably need to use a shorter wad like the DownRange or the Claybusters - both are shoreter that the Winchester WAA-12.

 

[BDodd]

While all above may have some truth, check your crimps for depth. If you can't measure the crimp depth as TjayE suggest above, use the old rule of thumb that it should be as deep as the thickness of a dime. If you're no where near that deep, adjust for more depth....breakemall....Bob Dodd

 

[TC]

1 out of 50 is a 2% failure rate. This would lead one to believe it is not a component or adjustment problem. If there was a component or adjustment problem the failure rate would likely be 10% or greater. Think it is the result of a fatigued or charred hull just based on what I have experienced in the past. YMMV.

 

[DoRaMa]

From: capvan
"Old style AA hull. 16.8 gr. of Clays, 1 oz. load. XL wad. I have no way of telling how many times the hull has been loaded. I don't keep track, just discard when there are any split lines. No wad pressure. I have always been told that this is unneccessary with the plastic wads. And remember, this is one out of 50-75 hulls. All the others are just fine. Bruce"

This load is OK. Weak hull or a shallow crimp or both at the same time.


Kevin @ 402-463-3415

 

[Shady Creek]

Neil, I'll buy that but with a plastic hull,with a good crimp I don't have them open up,papers I sometimes did. On one of my MECs I had trouble keeping the buffer in my Knockout loads, (without the overshot cards)so I added wad pressure,tweaked the machine until my crimp has a neat swirl that keeps the buffer in. I'm not trying to be argumentative,just trying to help.

flincher100,Don't tweak that loader?????Seems silly to me but what do I know. All I can tell you is from my experience.You are right though,1oz shot in a 1 1/8oz wad works great, the wad cup is full,shot does not scrub on the barrel,great patterns.

Merry Christmas and GOOD LUCk

Ollie

 

[krieghoff80]

capvan....and the rest of you.... the new aa hulls, the grays in particular...
have a two piece base....THE BASE WILL SOMETIMES COME LOOSE AND PUSH UP...
giving a "over filled" apperance, and at times causing the crimp to "bulge" out
... i told the aa rep. at the nsca championship(3 years ago) about my discovery, he said the factory had known about it for sometime....he wanted me to advise them of the lot number that the hulls came from.....also look to see if one of the wad pettles got folded over...again "overfill"....cut one open and look inside....you'll see the base has moved up...good luck