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I read somewhere that the 180 grain 40 S&W had pressure problems and was unsafe. Is there any truth to this?
 

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The 180 Grain loading was the first load brought out for the 40S&W. It is not unsafe, in fact, it is usually considered a mild loading relative to the lighter bullets. The 180s are generally considered less effective than the lighter faster bullets due to expansion/penetration factors.
Andy
 

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Nawth East Moderatah
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The problem lies in reloading. Excessive pressures in the 180gr. 40cal can cause Kabooms inunsupported chambers.

I have NEVER seen or experienced either, but have read the stories on several sights, including Glocktalk.com
 

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the 180's are a bit heavy/long for the .40case...although it is a factory offering, there is a "trick" to relaoading that weight. The cases get thick pretty fast, and that bullet is a bit long, so if it is seated in some cases, there is a visiable buldge in the case wat the base of the bullet. that buldge can be large enough to cause chambering problems (.380 and 9mm reloaders find the same thing when using heavy/long bullets).

Part of the pressure problem (leading to "ka-booms") may be related to internal case volume. Once you seat a 180gr. bullet to recommended OAL, will find that the internal volume of a .40SW case is just a hair LESS than the volume of a 9mm case when 115gr. bullets are seated to recommneded OAL. That's not much volume, so any amount of deeper seating (either by accidnet or by bullet movement during the feeding cycle) will raise pressure very quickly.
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Follow reliable manual data EXACTLY (esp. to OAL) an the 180's are useable in the .40. Is my prefered cast bullet weight.
 

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The Hog Whisperer (Administrator)
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Hmm, I've loaded 200gr. bullets in the .40, and didn't have any problems.... maybe the brass I was using was thinner?

Or maybe some 180gr. bullets have long truncated cone noses and this forces deeper seating? Hadn't heard this.

I will say this, Glocks (one of the first .40 pistols available) have very generous chambers and the hotter the load, the more pregnant the brass ends up looking. You can even see this with factory loads.
 

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The internal case volume measure kind of shocked me. Have been studies of the effect of small decreases in OAL on the 9mm, but none I've read on he .40...would bet taht the 40 pushing a 180 isgoing to have pressre increses just as drastic (or more) than the published 9mm data.

Some 40KaBooms may be from the bullet setting back in the case whne the round is cycled into the chamber...could well have started out at the right OAL, but feeding shortened it. A loose chamber won't be a help here..and the more unsuported case at the rear, the worst the effects could be when the round lets go.

BUT...I don't think the 180's would be alone in this...the 150's and 135's should suffer the effect as well (as will any semi-auto round that is allowed to have the bullet telescope back into the case). It's just that when you are dealing with a small volume to launch a large bullet, the effect is more pronounced.

For me, the 180's ar more for target shooting...I relaod them, but stop the load work up once (1) functiong is 100% and (2) accuracy is found. Velcoity isn't a serious consideration against peper tartgets.
 

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The internal case volume measure kind of shocked me. Have been studies of the effect of small decreases in OAL on the 9mm, but none I've read on he .40...would bet taht the 40 pushing a 180 isgoing to have pressre increses just as drastic (or more) than the published 9mm data.

Some 40KaBooms may be from the bullet setting back in the case whne the round is cycled into the chamber...could well have started out at the right OAL, but feeding shortened it. A loose chamber won't be a help here..and the more unsuported case at the rear, the worst the effects could be when the round lets go.

BUT...I don't think the 180's would be alone in this...the 150's and 135's should suffer the effect as well (as will any semi-auto round that is allowed to have the bullet telescope back into the case). It's just that when you are dealing with a small volume to launch a large bullet, the effect is more pronounced.

For me, the 180's ar more for target shooting...I relaod them, but stop the load work up once (1) functiong is 100% and (2) accuracy is found. Velcoity isn't a serious consideration against paper tartgets.
 

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I have heard these stories as well. I have loads for my 220gr Precision Bullets for the .40 that work quite well. You just need to work up each individual load in YOUR GUN to make sure that pressure signs do not occur prematurely. some .40's such as Glock's have very loose and unsupported chambers, with these guns it is espescially important to work up your own loads.
-Mike
 
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