Roll crimp question

[Grumpa72]

In my previous post, I mentioned that I was going to try my hand at .38 special. Here is a representative example of my work yesterday. With no history on roll crimps, is this crimp too heavy for a light load? The load is a 158 grain LSWC over Win 231 with 3.4 grains. The second question I have is whether or not the bullet on the left is too far out. It is set at 1.475 whereas the one on the right is set right at the top of the crimp groove at 1.465. Some have said not to bother measuring and just crimp in the groove and be done with it.

So, do these look ok?

Oh, and thank you all again. This WAS quite simple and easy. The biggest issue is that the charge is so small that it takes some effort to verify that I have actually dropped powder. I can see how a squib can occur with this powder and load.

68398

[btroj]

I would accept either one. Crimp is in the groove, that is what matters.

[44man]

Looks good. Don't bother measurng.
I seat to the top of the crimp groove like the one on the right.

[Grumpa72]

Thank you both. Is that crimp too severe or is it "just right"?

[44man]

As long as you do not see a bulge in the brass below the crimp, you are OK. You actually need less then you might think.
I see good case tension so crimp is only needed to prevent boolit pull under recoil.
Load six, shoot five and look at the last round. You will find good tension with a moderate crimp is just fine.
I shoot a lot of Lee boolits with chicken scratch crimp grooves. I need to back off the crimp but they hold just fine. The Lee does not pull even in my .475.
Your boolit has a great crimp groove, just roll to touch lead, not force into it.

[mdi]

Both look good. The one on the left looks like a "medium to light" crimp, not excessive, and the one on the right looks mild (and perhaps the case mouth is hanging up on the driving band as it's being crimped. Seat bullet a bit shallower.), but also quite acceptable. In my magnums I usually put a heavier crimp, but yours look good.

[runfiverun]

i'm more a guy on the left crimper.
I probably wouldn't even crimp for the load you are using.
how's about a report back on the smoke screen you see when shooting these?

[JWFilips]

I have always been baffled by roll crimp terminology: Medium, Light, Heavy etc.
since I never got a good explanation for the types of roll crimps and how to gauge them, I formed a somewhat repeatable method that seems to work for me.
If I'm loading light target loads with the .38 spec I will run the case with the properly seated boolit up into the press then turn down my crimp die until it touches the top of the case and there is resistance. I then drop the ram & tighten the crimp die down another 1/4 +1/8 turn. This gives me a nice roll crimp Not sure if this would be considered light , medium or heavy. I know I have gone as far as 3/4 turn for my heavy .357 mag loads

Since I can always come close to duplicating crimps with this method I have been using it…… Just wish I knew if there was a formula for this method?

[Grumpa72]

i'm more a guy on the left crimper.
I probably wouldn't even crimp for the load you are using.
how's about a report back on the smoke screen you see when shooting these?

Thank you all. RFR, are you saying that Win 231 is too smokey for you or ...? So far, I only have shot 30 of these, 10 in each powder charge and I was looking for POI and group size. I will report back on the alleged smoke screen.

[44man]

For sure. Crimp is just too hard to explain. I have trouble myself.
I have seen full profile crimped factory loads let boolits pull and lock up a revolver in two shots.
The thing I don't like is when someone says crimp aids powder burn, not true. Just keep the boolits in the brass under recoil.

[runfiverun]

yeah, 231 and that hard lube usually gives me a good poof of smoke.
don't stop me from shooting it though.
a 358477 and 4 grs of 231 has produced the best groups in my d/w revolver.

[Grumpa72]

Thank you all for your time, patience, and knowledge. I wound up backing the roll crimp off "just a smidge", perhaps not even 1/4 of a turn. Then I backed out the seating die to 1.470, smack in the middle of the two in my photo. It looks good, fits the cylinder just fine and I will be shooting tomorrow to see how it does in my Colt 2" Cobra. I already know that it shoots very well in the Colt Commando.

I do appreciate it. Now, if I can only get the Lee casting dies back in stock at the various vendors for 9mm and now .38 Special.

[41 mag fan]

I have always been baffled by roll crimp terminology: Medium, Light, Heavy etc.
since I never got a good explanation for the types of roll crimps and how to gauge them, I formed a somewhat repeatable method that seems to work for me.
If I'm loading light target loads with the .38 spec I will run the case with the properly seated boolit up into the press then turn down my crimp die until it touches the top of the case and there is resistance. I then drop the ram & tighten the crimp die down another 1/4 +1/8 turn. This gives me a nice roll crimp Not sure if this would be considered light , medium or heavy. I know I have gone as far as 3/4 turn for my heavy .357 mag loads

Since I can always come close to duplicating crimps with this method I have been using it…… Just wish I knew if there was a formula for this method?

JW...you're using the method all of us use. If it looks good, it's holding the boolits to the seating depth you put them at, and it's not cutting into the boolits, then you're good to go.
Something I heard a long time ago and never really tried is the amount of roll crimp can affect accuracy.
I roll crimp what I call the standard way or pretty much the same way you are and I get good accuracy on my loads, so why change what is not broke!


Thank you all. RFR, are you saying that Win 231 is too smokey for you or ...? So far, I only have shot 30 of these, 10 in each powder charge and I was looking for POI and group size. I will report back on the alleged smoke screen.

RFR like the smoke, besides it smells good, he has a major mosquito problem and it helps keep them at bay!!! :bigsmyl2:

[Cherokee]

I shoot a lot of the 231 load with that type boolit, very accurate for me and easy shooting. I use a light crimp. The one on the left would be my choice. Actually, I have been known to taper crimp the light 38 special loads - works fine.

[easymoney]

Both look good to me. It appears I gauge my crimp like everyone else. I screw the die down until it touches the case mouth, back out the ram and screw the die down about a quarter turn. Raise the ram, set the crimp and examine the results. A quarter turn is never too much so there isn't any danger of crushing the case mouth or the bullet. I mark my dies with a Sharpie so it's easy to distinguish the amount of crimp being applied. For revolvers I don't worry too much about OAL, I just make sure the crimp is in the groove and set it. I base the amount of crimp I use on what load is for. For target/practice loads a light crimp has proven sufficient. On defensive loads I'll increase the crimp a quarter turn or so. The defensive rounds are loaded hotter and much more likely to cause bullet movement and when everything is on the line the last thing I need to worry about is a bullet sliding forward enough to lock-up a revolvers cylinder.

[runfiverun]

no kidding on the skeeters.
the river is just down the hill and the lake is less than 2 miles away.
and the little buggers work like a wolf pack.
you are swatting them on your arms and they are biting you on your head.

[Grumpa72]

I have learned quite a bit from all of you.

Thank you all.

[dgill99]

I would go t]with the one on the left