Guy Neill

You may consider the 9x25 was over gassed since it would drive the gun down, as I understand.

Try test groups with each and see if there is a notable difference.

It's nice to have clean brass when sizing.

Recoil is historically reported as the kinetic energy of the gun. Reference: Hatcher's Notebook SAAMI (as taken from the British Textbook of Small Arms 1929)

He's in the Portland, OR area. He has a website, but I don't know about videos. Tyler Firearms Instruction | Competitive Shooting

Keith Tyler (GM) has classes on movement.

Since the powder gas works the comp. the powder with the heaviest charge weight will deliver the most gas at a target power factor.

Recoil is looked at as the kinetic energy of the gun, with the gun velocity found with a momentum balance, as shown in the numbers given earlier that include the gas momentum. The gas jet does do something, but to what degree is unknown. If it did nothing compensators would not work. Finding the thrust cannot be accomplished easily, and since we are already using the gas momentum in the momentum balance, it may be unnecessary. Thrust requires the mass flow rate and the gas velocity at the muzzle, at least. A muzzle gas velocity can be approximated only if we know the actual chamber pressure, and varies shot to shot just as the chamber pressure does. We normally do not know this. Even with chamber pressure values from a pressure gun, and approximate muzzle pressure. I am also not certain what time element would be used in determining the mass flow rate. Thereby, historically, any jet effect adding to recoil is ignored.

Most PCC's I've seen have compensators. Compensators work better with more gas, so the lighter weigh bullets, with more powder, give more gas. I've not shot a lot of PCC, but that's the way I would approach it, leaning to using the 124 grain bullets as the middle ground.

Power factor is a momentum value. Definitely, if you are shooting the bullets at the same velocity, the heavier will recoil more. However, you are normally shooting the bullets at the same power factor so that the recoil is the same. The heavier bullet, going slower for a given power factor, will take longer to exit the barrel (though not by much), so the recoil is delivered over a longer period of time. Most will not likely notice the time difference. The choice comes down to what feels best to the shooter, delivering quicker follow-up shots and accuracy. Other factors include the moment arm and the amount of powder. Since the powder charge plays a part in recoil, and the heavier bullets normally use less to make a power factor, the resultant feel is different since the force on the gun changes. As an example, taking some charge weights from one of the reloading manuals, we have, for 9mm, Bullet Velocity Charge Recoil Force PF 115 1130 5.2 2.52 6.4 130 124 1048 4.9 2.47 5.9 130 147 884 4.0 2.34 5.6 130

How about these? D45 - Black Lacquer Gun Stock (herrettstocks.com)

If ruling out anything to do with the comp, bullet tumbling would relate to the bullet, the velocity and the twist. What is your barrel twist and bullet velocity? For a 124gr making a 170 power factor. a 1:10" twist will normally give almost 100,000 RPM. A slower twist rate will, of course, give less RPM. What RPM is needed for bullet stability would need to be determined. Does your friends gun have the same twist rate as yours? The most common cause of tumbling is low velocity (giving low RPM). Causes of low velocity can be bullet diameter, barrel bore diameter or load. Assuming the ammunition shoots well in your friends gun, it suggests a problem with your barrel. Larger bore diameter, less rifling or slower twist rate. Thus, a number of things to investigate.

i had understood that the "Glock bulge" had to do with the case head that expanded such that the sizer die could not totally iron it out. Thus the various roll sizers and push through sizers. Nothing to do with the primer that I have heard.

With regard to ambi thumb safeties, it's mostly what lever/paddle size and shape you like, and what method of joining the two sides. The EGW mentioned used an extended sear pin to keep the two sides together, as I recall. Others may use the original Swenson method of the through pin joining in the middle with a tongue in groove sort of arrangement. Some say the tongue in groove is prone to breakage, but I have never seen it, though I expect it has happened. Regarding the front sight. I believe the only way to really "fix" the two holes is to weld them, then proceed with the new sight installation. Talk to you gunsmith.

Look at the inside of the slide where the sight is mounted. If there are two holes, replacement will be difficult as those are no longer made. If there is a single staking hole, then replacement is to find a suitable tenon sight to replace it. I think Series 70's had the narrow tenon. The two hole mounting was to provide greater strength. Alternate is to have a dovetail milled into the slide to take one of the various dovetail type sights. Will you be changing the rear sight as well? The problem with larger front sights (larger than teh factory) is that the tenon may not hold as well. This is a primary reason dovetail sights became popular. Why do you want to change it?

Just thinking out loud, but the primer does not look as if it saw extreme pressure. Also, the rupture extends beyond the extractor groove, suggesting an out of battery firing. With the number of rounds fired prior to this one, there could have been some debris that prevented the slide from going fully into battery. With the light springs commonly used in Open guns, it may have allowed the slide to be far enough to allow the disconnector to move, but not fully into lock-up.

Just reporting what the CCI techs told me a while back. Whatever the black pits are, they will erode a chamber if the case ruptures.

The Redding T7 drops the primers through the ram, exiting a tube to channel them where you want. The new RCBS Rebel press also drops them through the ram.

I believe Wilson has dropped the 38 Super. Nighthawk may be a consideration as well. Or, perhaps, shops like Cylinder & Slide or similar.

Take a look at some of them and see if you see any tiny black dots on the case wall. Each black dot is a corrosion pit. They are very small. Aluminum corrosion is nothing like brass corrosion. Aluminum cases that crack with the crack being a straight line are due to scratches. Cracks that are jagged are a connect the dots where the crack propagated from corrosion pit to corrosion pit. Both will commonly damage the chamber of the gun.

While small rifle and small pistol primers have the same dimensions, the large pistol and large rifle differ. Large rifle primers are taller than large pistol.

Most, if not all, CCI Blazer aluminum cases are now Boxer primed. The main reason not to reload aluminum cases is that resizing scrapes through the protective coatings, exposing the bare aluminum to corrosion. Aluminum corrosion takes the form of pits into the metal, The coatings are to protect from corrosion and provide lubricity. Firing a corroded aluminum case has a great chance of eroding the chamber.

If you have a gauge, or using your barrel, see how well some of them drop in as an assessment. Many like to resize even new cases - especially with progressive loaders, but it may not be needed . It's likely more common to size new rifle cases than handgun to true the neck. Chamfering the ID helps prevent the cases from sticking on the expander. which can sometimes leave slivers of brass if the corner is pinched off by the expander.

You may want to tumble them a bit to add dust to help in the sizer, if you will size them before loading. Also, chamfer the ID of the case mouth.

Running some numbers for a 45 Auto With a charge weight making 170 PF with a 200gr bullet gives a recoil of 5.2 ft-lbs. Changing to a 185gr bullet with the same powder charge changes the recoil to 4.1 ft-lbs. Velocity went down for the lighter bullet at the given powder charge.