Moon clips and crimping

[jpuke]

I've been thinking about getting an S&W 625 in 45 ACP and I've read all the posts I can find but I still have one question - can you roll crimp if the revolver uses moon clips?  My guess is yes since the headspacing relies on the clip but if I'm wrong let me know.  Thanks

[John Traveler]

Yes indeed, you CAN roll crimp your .45 ACP reloads when using the half-moon or full-moon clips.

I guess the question is WHY would you want to?  Correctly assembled .45 ACP loads should be LIGHTLY taper-crimped.  Neck tension alone is enough to give you good bullet pull if your expander plug and bullets are proper size.

Another thing about relying on moon clips for your S&W M625 revolver.  A bent or distorted half-moon or full-moon clip can cause misfires by lifting the case off the cylinder and not letting the firing pin impact fully.  Plus, there may be an occasion where you NEED to fire your cartridges without a moon clip.  The roll-crimped ammo would definitely give misfire problems.  Unlike the M1911A1 pistol, where firing pin protrusion is almost unlimited, the S&W has only limited firing pin protrusion.

HTH
John

[jpuke]

So do the rules that apply to revolvers - ex: the bullets sliding out of the case during recoil- not apply to 45 ACP revolvers?  I was asking about the roll crimping because I've had some 45 Colt slip further out of the case if I don't put enough crimp on them.  If I don't have to worry about that, all the better because it'll cause less wear on the case mouth.

[John Traveler]

Exactly.

The heavy crimp/roll crimp is NEEDED on the .45 Colt round to prevent a bullet jumping the case under recoil and tying up your cylinder.  You'll notice that there is not much clearance between the end of a .45 Colt bullet and the chamber mouth.

The heavy crimp/roll crimp is NOT needed on the .45 ACP because the chamber ledge helps to prevent the bullet jumping out of the case.  PLUS, the shorter .45 ACP round means the bullet would have to creep much farther out of the chamber to jam your gun.  I've never had it happen while firing .45 ACP, and have only rarely had it happen while firing .45 Colt.

Factory (military) jacketed ammo uses asphaltum (tar) sealant to hold the FMJ bullet in place, combined with a tight bullet-to-case assembly.  You can duplicate this in jacketed bullet handloads by using a Q-Tip swab to brush on tar thinned with acetone.  Let dry before loading.

With lubricated lead .452" bullets, use an undersize expander plug (.450"-.451") and a tight sizing die (.448"-.449") to achieve the tight case-to-bullet fit.

Again, a good reason NOT to use a heavy roll crimp on the .45 ACP for revolvers is increased likelyhood of misfires.

I forgot to add:  A good law enforcement friend got an extra crease across his belly one night.   It happened when his duty gun misfired when using, you guessed it: a bent moon clip in his revolver.  Luckily his second and third shots fired, and the bad guy wasn't able to shoot again.

HTH
John

[De41mag]

jpuke;

I've got a 625 in 5" barrel and use the moon clips. (full)
I haven't experienced any problem with a taper crimp.
As a matter of fact it is the most accurate revolver I own.
I shoot two loads in it, a 185gr. cast bullet from Leadheads ahead of Bullseye and a 230gr. FMJ ahead of WST. And I dont have any problem of bullets jumping foward. A taper crimp die will work just fine.
Probably shot 3000+ rounds through it so far and had it only a year.  :grin:
Dennis.

[palgeno]

I have a 625 from the Performance Center built on the N frame. I have used some heavy loads including .45 Super and am only using a taper crimp and am using full moon clips----recoil has not caused any problem of bullets backing out with any of the loads.