Guy Neill

Is there any pattern of barrel twist rates - such as fast twists shooting the load well and slow twists not? If so, faster velocity may help in the slow twists - assuming those are the ones not shooting it well. Guy

Sorry, I didn't see one for left handed. As SiG Lady said, though, you should be able to switch the right and left sides and have it. Guy

See if this is the target you are looking for: http://is-lan.com/challenge/images/Pistol-Correction.pdf Guy

Large rifle primers are "taller" than large pistol primers, with the primer pockets correspondingly different. There is overlap, with deep large pistol primer pockets and shallow large rifle primer pockets, but, in general, you should not interchange large primers. The worst case situation is where the large rifle primer is seated in a shallow large pistol primer pocket. This could result in a slamfire in an autoloading pistol, and almost definitely will bind cylinder rotation in a revolver. Either save them for use in a rifle, or see if you can trade them at the next gunshow. Guy

Quite right. The original premise was that the added weight was assumed to affect the internal volume. As has been demonstrated through water volume, the added weight does not always greatly affect the internal volume. Rim diameter and thickness, along with the diameter of the bottom of the extractor groove can affect weight without affecting internal volume. Thanks. Guy

Eric, I understand your concern with the 40. As I tried to point out in a column many years ago, the hoop stresses in the 40 are greater than for a 9mm simply because of the larger diameter (at the same pressure). Many of the earlier 40 probelms I believe also related to the amount of material in the cases. Some of the earlier cases had relatively flat bottoms inside, minimizing the amount of brass at the transition between the web and case wall. This is the exact point where they were blowing out. While I can not say with absolute certainty, I believe the factories have changed the 40 cases, adding a radius at the inside bottom, allowing more material in the case web to wall transition. I do know that the number of blown 40's I saw while still with Speer reduced significantly in recent year, indicating, to me, that something had changed. Still, there is still ammo out there with the old case style and, I'm sure, in the reloading arena, so care should still be exercised. Take care. Guy

You might check Alma's post above. He has experienced his Glock cracking the breechface using 9mm Major. I have not seen any other cracked slides personally. I've been told Bob L has seen some, but I have not had a chance to talk to him about it. In the past, I have seen 1911 45's crack slides. It was either at the ejection port, as someone else described, at the left rear corner, or at the end of the lightening cuts at the bottom front of the slide (when everyone was shoting 5" 45's). One reason Colt removed the bridge of metal at teh slide stop cut out on the Delta Elites was because of the tendency of that bridge to crack. Another area that has cracked is at the rearmost portion of the dust cover, though this commonly has more to do with the way the gun was fitted. Strangely, as I think about it, I don't recall ever seeing any cracks on the right side. They've all been on the left side of the slide and frame. Okay, I take that back, I do recall an early Detonics that had a frame crack in the grip area on the right side. When the lead free ammunition first began selling, I also saw breech faces that were peened by the primer in various guns. Ultimately, I expect they would have cracked as Alma described. This will likely be common on any guns where the slide is case hardened instead of through hardened and the breech is pounded by the primer. Slides with lightening cuts may have a slightly greater tendency to crack, depending on where the cuts are, and their configuration. Even if there is no stress raiser from the cuts, the increased slide velocity may see greater impact that could lead to increased stresses or wear. Like any tool, however, the guns are subject to wear and will need maintenance and repair if they are used. Every sport has its price, and periodic repalcement of parts or guns is part of our price if we are actively shooting. It's important to inspect the gun and all the pieces when you clean the gun to find things as early as possible. Guy

Whatever the avatar actually is, it makes me think of the air rings we did while scuba diving. Guy

Green ammo will contain no lead - in any form. Such ammo normally has a sintered copper bullet, but it could use some other form as well, as long as no lead is present. Green ammo also uses lead free primers. Semi-green ammunition may be like the CCI-Speer Cleanfire having lead in the bullet, though totally encapsulated, and a lead free primer. They also have (or had) some using sintered copper bullets as well. The greatest problem with lead free primers is that they produce more thrust against the breechface. This is why you are seeing small primers being used in some, such as Winclean and Federal Non-Toxic, as well as some crimping the primers (Federal). Earlier attamps saw the flash hole enlarged to reduce the backthrust. Prior to these sorts of changes, guns were having the breechface peened (damaged) from the force of the primers. I don't know if the changes have totally eliminated peening, but they have certainly reduced it. Costs are generally higher for lead free ammunition, and the lead free priemr technology may see a greater number of misfires - somewhat dependent on local weather conditions. The lead free primer mixes tend to be moresensitive to humidity conditions than lead styphnate primers. Guy

Call Bomar - they will likely send a replacement pin or two, or send the sight to them to reassemble with a new pin. Sorry, I don't have their number at hand, but they are on the internet. Guy

Double check with Remington on the twist rate. Many of the newer guns - especially those labeled "tactical", or some such, have faster twists. Of course, the faster twist limits the lightweight bullets in many instances. Guy

I greatly appreciate everyone's input and comments. EricW - Yes, the 40, operating at the same pressure as the 9mm, will give higher hoop stress. The early 40 cases had too much of a cylindrical inside bottom and most, if not all have changed the cases so that there is more material (radius) in the transition from the web to the sidewall. Again - thanks to all. I don't mean this as an end - if anyone has more information, let's hear it. Guy

I seem to recall Cylinder & Slide having a tool to make compressing the spring easier. You might check with them (402-721-4277. Guy

What is the wall thickness at the case mouth. It sometimes happens that the brass ends up thin, so that a normal sized, or on the larger side of the tolerance size sizer won't adequately size it. This may be the situation if the case wall thickness at the mouth is on the order of 0.010". If the brass measures normally (0.012 - 0.014" thick) you might try a different sizing die if you have one. Have you tried seeing if a bullet will go in the sized, but not expanded case? If the bullet will not drop in after only sizing, then the expander comes under suspision. Also, what are the bullet diameters? Guy

I believe Kirk is deceased. Guy

Last I heard he was shooting Cowboy. Alias of "Idaho John", I believe. No first hand knowledge, though. Guy

The SciFi channel has been advertising today that Firefly will begin next Friday. Guy

No specific timeline. I'm trying to refine the theoretical variations of the 9mm Major to the reality people are seeing in their guns. The next colum tries to address these differences - assuming I can get it to a form the editor likes. Thanks to all for any data/information you have. Guy

I would look seriously at I35 all the way to US 36 and turn right into Hannibal. Guy

The couple of times I've had a Bomar hinge pin begin to come out, it indicated the pin had broken. Of course, I don;t think I would have ever noticed a 3000th of an inch. Mine came out a 16th to an eighth of an inch. Guy

The first time I used HS6 in the 45 was an early Nationals where I used 230gr jacketed bullets. The powder did well, except it has a brilliant white flash in the dark. If you will not be shooting in the dark it shuld do okay. In the dark I would want a different powder. Guy

I would expect most USPSA clubs would have no argument about shooting a single action revolver. Ity's been done before. If that is what you (she) has, and that's what she wants to shoot, she should. It's about fun and enjoyment first. Guy

In my column in Front Sight, I asked for feedback on people's experiences with 9mm Major. It was subsequently suggested that I post here and ask the same question. A good suggestion I am following. I read through the topic on 9mm Major, and noted that the variations reported, as with the SD's did not seem larger than commonly seen in various loads. That is good, for the theoretical calculations suggested much more potential for problems that should show up in larger velocity variations. I am continuing to research this and would appreciate any experiecnes any of you may have with, especially, 9mm Major, but anything with the 9mm case would be of interest. As I pointed out in the column, I found over 9 grains difference between the lightest weight and heaviest wight 9mm Luger cases I recently weighed. This should significantly affect the internal volume and cause different pressures with the same load, given a mixture of cases. I have had at least one comment concerning 9mm Major cracking slides, but I have not yet been able to follow up on it. Of course, cracked slides can result from other factors as well, so much more information is needed before any conclusions can be made. I appreciate your help and comments. Guy

I vaguely remember a movie called "Cherry 2000" (as I recall) that seems similar to that. I know it was in the desert a lot, but don't remember a lot more. Guy

While CCI and Federal are part of ATK, I don't know exactly what Federal did with their Match primers. For CCI, the BR (match) primers were done by personnel having a history of consistent production. The CCI BR priemrs had a narrower tolerance than the standard primers, so it was important to use personnel with a history of consistent, good results. The priming compound is inserted manually, as efforts over the years to automate the process usually end with a lot of damage to equipment and people. Thus, chargers (those personnel working with the priming compound) showing the most uniformity and consistency are those assigned to the match level primers. I would expect Federal and other primer manufacturers would use a similar criteria. I would not expect that this has changed at CCI since they and I parted. Alternately, some manufacturers could use test results alone as a criteria for designating match lots. This was done in rimfire ammunition at CCI. Those manufacturing lots testing exceptionally uniform in results could be sidetracked to the match packaging. Testing normally looks at sensitivity and the amount of priming compound. Guy