Overpressure rounds in an auto pistol?

[Ohio Rusty]

I've mentioned before I've always been a revolver shooter. My next pistol will be a .380 auto pistol. In reloading for a revolver, the approaching signs of high pressure were easy to see......... The empty hard to eject from the cylinder, the flattened primer from the shell pushed hard against the breech face, a crack forming at the mouth of the case, etc. With an auto pistol, the case is ejected upon firing and not contained in a cylinder. Other than a cracked empty, how do you determine high pressured in an an auto case? I do not have a chronograph, so my inspection has to be visual. The reloads I'm alluding to will be for .380, using VV N310 powder to start ..... I may even try Trail Boss in the shell ...
Thanx .........
Ohio Rusty

[Blammer]

look for the same flat primers for high pressure.

also, take some factory ammo and shoot it for a basis.

look where the extractor grips the case, is there a bite mark? if it's bigger than the factory stuff you've got high pressure. Is the rim of the case bent? Do you have a bulge for "case head" seperation. Is the action "slamming" back into the gun? vs your factory rounds.

those are some indicators of high pressure and you need to back off.

of course standard ones are flattened primers, accuracy getting worse, etc...

[Johnch]

Another thing that CAN show extra pressure is where the cases end up ( not allways )

If your pistol normaly puts it's emptys in 1 small general area
And your new reload flings them 2 times as far or just a ways farther or to the left

There is a good chance your load is to hot

My 9mm Hi Power puts all the emtys in a 4' circle 10' to my right and 6' in front of me if I don't have the tarp up

If a new load threw the brass farther out , I would look into my new load

John

[SharpsShooter]

These guys are leading you right. The same pressure signs you see elsewhere will be apparent in the auto pistol. The extractor is an additional sign of course and I would add that a chronograph is not always a good indicator when we look for excessive pressure. The case always tells the story.

SS

[TAWILDCATT]

I would suggest using the manual for 380 charges.the 380 pistols do not lock up.and you could harm them from excesive shock.I do know older ppks cracked frames with factory loads.I would also use bullseye or 700x.you dont want to magnumize the 380.I shoot a FI 380 that does lock.
-----:coffee: ----:Fire: ----:coffee:

[mike in co]

I WOULD SUGGEST GETTING A CHRONO !

IT IS THE TOOL THAT WILL ANSWER THE QUESTION YOU JUST ASKED.

you can compare existing data against how factory ammo does in your gun, and then how your load do.

eveything else is just maybe/ballpark ....

its a small short low pressure round.....small changes in oal and powder will make big differences.

mike

[Charley]

As noted above, most , but not all, .380s are built on blowback actions. Inertia and spring pressure are what keepe the breech closed upon firing. Excess pressure will usually resort in the brass being distorted, and looks very different from normal dings and dents. I've seen some cases look like they almost had a belt, due to the breech opening before the bullet exited the barrel and the pressure dropped off.

Follow the manual with autoloaders, especially blowback designs. The few extra feet per second you might gain won't make up for the battering the frame and slide will undergo. Find a load that will function the action, and use it.

[Dale53]

The principal problem with trying to look for "Pressure Signs" with normal revolvers and pistols, is quite often there is NO warning before you are way over pressure. Pressure higher than normal may not cause catastrophic damage but can accelerate wear. I have long used Hodgdon's data as it includes pressure information with each load.

Small cases like .380's can be especially troublesome - a slight increase in powder charge can cause a disproportionate increase in pressure.

Use a COUPLE of good manuals (Lyman and Hodgdon's) and follow them closely. As others have stated, a chrono can help. Take particular pains to insure that bullet seating depth is carefully followed (deep seating bullets can cause serious pressure increases).

On the other hand, there is no reason a careful handloader should needlessly worry about loading these small cases. Just "pay attention" to details and you'll have few problems.

Dale53

[Cherokee]

It does not take much to fill the case so be careful if using a progressive that you don't sling powder out of the case. 380's are fun to shoot.:castmine:

[DanM]

If you end up getting a used .380 blowback, the first thing I would do is replace the recoil spring with a new one. Depending on availibility, an extra power Wolff recoil spring is a good addition to any blowback pistol. Unless, of course, you are shooting reduced target loads. My blowback experience is limited to my Makarovs in 9x18, a similar cartridge, and very easy to load for. I always use a wolff 19lb. spring in them. Come to think of it, a Mak in .380 would be a good choice. A PPK is nicer, but not a bit more accurate or reliable. You do need a chronograph to know 'where you are at'. Book loads should be safe, but are almost never 'right'. Measured velocity seldom equals published velocity, at least in my experience.