Been reloading 9mm for a couple of years for a couple of PCR's I own and never had any problems. I recently acquired my first 1911 9mm single stack and I am having trouble with the rounds not plunking.
• No two 9mm chambers are the same. Each manufacturer cuts their chambers differently and the reloader has to accommodate this in their thinking and calculations.
• 9mm Luger is a small round, but it is NOT an easy round to reload. In fact it is one of the most difficult handgun rounds to reload correctly. As stock brokers are fond of saying, "
Past performance is no indicator of future results." The fact that there was no trouble in the beginning only indicates that you were dealing with guns with lax chamber dimensions and as a result may have adopted lax reloading standards.
Dimensionally everything checks out with the exception of the OD of the case where the bullet base is seated. This diameter is 1.385" on some of the rounds. These are the rounds that aren't plunking.
I am not trying to embarrass anyone, but rather point out some glaring errors to hopefully educate...
• No, sorry to say that is
not a true statement. If 'everything DID check out', then the rounds would fit. Something is missing.
• There is no dimension on a 9x19 Luger round as high as
1.385". Reloading demands a level of
precision and attention to detail that is missing here.
I adjusted my taper crimp die down so that this diameter is 1.380". This causes the case mouth diameter to be 1.360". This also the first time I have been able to get these rounds to fit in my Wilson case gauge. I am concerned that I may be crimping so much that I am swaging the bullets.
• Again, there is no dimension on a 9x19 Luger round as high as 1.380".
• There are at least 3 events that can keep a 9mm cartridge from chambering...
1. OAL - Every bullet has a different ogive shape. These differences
must be accounted for. In an auto pistol, bullet-to-barrel fit is
everything. OAL dimensions given is the manuals are NOT recommendations.
2. Crimp - Because the 9mm chamber is tapered the 'taper crimp' must be precise. The diagram in your reloading manual shows the TC at a dimension of 0.380", which is a
maximum. Therefore your best taper crimps will be in the 0.376 to 0.379" range. No more, no less. This is NOT a "
if some is good, more is better" situation. Aim for 0.377" and variations will all fall in an acceptable range.
3. Excessive brass dimensions - Case head expansion due to being shot in a firearm with excessive chamber dimensions, OR brass from super-high pressure rounds like 9mm Major. Case head dimensions in excess of 0.391" simply will not fit some chambers.
Additionally, sizing dies cannot resize a case in that area. Bottom Line: Brass fired in your PCR may no longer be suitable for your 1911.
All 3 of these situations need to be checked and accounted for.
• The Wilson case gauge is a great tool, but is no substitute for the barrel. When you start reloading for a new gun, you MUST use the barrel as the cartridge gauge. The barrel is "she who must be obeyed". The case gauge always has limits and cannot tell you everything the barrel can tell you. IOW the gauge only gave you half the information you needed. Thus you were blind in certain areas of cartridge construction.
In short, we are not baking cookies where we can get "pretty close" and things still work out. Some of the adjustment tolerances in reloading are smaller than a human hair. So you'll simply need to "up your game" to play in this league.
