Empirical Firearm Statistics.

[GLOCK18]

My favorites

Glock
Sig 226
Barrett 92F

 

[Lightraven]

My Glock recoil spring guide rod broke, jamming the gun until a Glock qualified armorer could pull it apart and replace it with a new one. After that, the gun needed a slap on the butt (of the magazine) to lock into battery every 30 rounds or so. Not my idea of perfection, so I sold it and used proceeds towards the XD and haven't had any problems yet.

I saw a Navy SEAL's Glock go down last weekend during a night fire. They pulled it apart, but I don't know what the diagnosis was.

Glock requires a trigger pull to disassemble, if I recall. The XD requires a slide lock first. For a new gun owner, that might be a very, very important feature. I also like the XD's physical loaded chamber indicator. It's really a good thing, no matter how often you press check.

 

[Bullzeyebill]

Lightraven, how long ago did you get rid of your Glock? How many years did you own it? Used it a lot? Wondered if wear and tear broke down that part, or bad part to start with.

Bill

 

[Benson]

As much as I respect guys like the late Mr Cooper, if they make a comment that goes against the laws of physics and it turns out that he wasn't just kidding I'm going to have to dig deeper into the question. Just my inquisitive nature I guess. :)

FWIW, I don't see it as a necessary violation of physics -- if gripped too solidly, I can see how a slide with an overly light spring could rebound and cycle too quickly for the magazine when held solidly, but cycle properly with a normal grip. Obviously, it's a design error, but I don't see the physics issue.

 

[RyanA]

While I was sitting around in physics today I thought of another way to figure out failure rates, although in relation to ammo only. Say out of a brick of 500 rounds there is one dud. So say that the capacity of the firearm is 20 rounds so that = (subscript 500 [sorry, I have no internet skills]) P (permutations) (subsript 20) 500P20. So that means 500! (500! =500x499x498x497...2x1) divided by 480! (500-20) Which basically equates to 500x499x498x497x496x495x494x493x492x491x490x489x488x487x486x485x484x483x482x481= some really enormous number which is equal to the number of possible combinations of rounds (consider each round like a unique unit numbered 1-500, one of wich is a failure.) So out of this enormous number (btw, if someone has a really bad arse calculator/abacus lemme know) EDIT: I thought it over again, everything I've came up with after this point is inaccurate, I need to re-think this for a bit. Maybe 20!/500!/480! I'll have to check with smaller numbers.

Another thing that might be of interest is if we could get the masses and velocities of different bullets, that way the linear momentum, ke and grav potential energy at the top of the arc could be computed.:naughty:

 

[Lightraven]

Lightraven, how long ago did you get rid of your Glock? How many years did you own it? Used it a lot? Wondered if wear and tear broke down that part, or bad part to start with.

Bill

I bought the Glock 27 .40 subcompact in 1996 or 1997 and the recoil guide rod broke within a year, with very few rounds--a couple hundred, at most. Glock sent me two new ones and they didn't have any problem. I then bought a Lasermax internal laser guide rod and used that. I never shot the Glock much (by my standards)--my duty weapon gets much more use--but every time I did, it hung up every 30 or so shots. I replaced the lasermax with both guide rods, got a Wolff magazine spring, lubed the gun more, but nothing helped. I talked to a Glock armorer and he thought limp wristing. I thought, "That isn't a problem with my other .40 guns." I did get pretty good at "tap, rack, bang."

Somebody made me an offer while I was still pondering the new XD subcompact and I accepted. I sold the Glock in 2006, I believe. The guy who bought the Glock gave it to his son. They both have experienced the same malfunction (which I warned him about before the sale), but is cool with it since it his kid's range gun.

 

[Patriot]

Another thing that might be of interest is if we could get the masses and velocities of different bullets, that way the linear momentum, ke and grav potential energy at the top of the arc could be computed.:naughty:

That could get ugly really fast.....lol. :sssh:


There are several good ballistic programs available for the PC is you're interested.

 

[PhotonWrangler]

That could get ugly really fast.....lol. :sssh:


There are several good ballistic programs available for the PC is you're interested.

I'm interested, Patriot. Got any suggestions?

BTW I'm considering renting a high speed camera and setting up at a range for analysis of trajectory and pitch.

 

[Patriot]

I've got a lot of experience on the Niteforce ballistics program.

Here is a pretty good review of it:
http://www.chuckhawks.com/nightforce_ballistic_program.htm

I've also tinkered with the one from Remington and Silhouette Ballistics but of those two the Remington is easier to learn.

In the end it kind of depends on what end of the shooting spectrum you're on because some are geared for preloaded ammo, or hunting, or silhouette, or some a little of each. I only named these programs since I use them but if you dig into the subject further there may be ones that people like more.



And just so you know Ryan, I think you're idea is great but there are whole books dedicated to ballistic charts. The possibilities are nearly infinite so we wouldn't scratch the surface of even 1% of it if we started listing stuff here. :)

 

[Patriot]

BTW I'm considering renting a high speed camera and setting up at a range for analysis of trajectory and pitch.

I forgot to respond to the high speed camera thing. That sounds very interesting, scientific and expensive...lol. Too bad I don't live near you because that sounds fun as heck.

Depending on what you're trying to measure, a chronograph and ballistics program pretty much covers the data that people are usually after.

 

[PhotonWrangler]

I forgot to respond to the high speed camera thing. That sounds very interesting, scientific and expensive...lol. Too bad I don't live near you because that sounds fun as heck.

Depending on what you're trying to measure, a chronograph and ballistics program pretty much covers the data that people are usually after.

Thanks, Patriot. I'm actually looking for anomalies like tumbling.

 

[Patriot]

Thanks, Patriot. I'm actually looking for anomalies like tumbling.

Are you key holing in paper or just having accuracy issues?

 

[Bullzeyebill]

Which bullet in which weapon might be tumbling? Sort of unusual with modern ammo. I had key holing issues in the past, but usually with reloads, for example trying out very long bullets in a 357. Need the right combo of velocity/sectional density/ballistic coefficient.

Bill

 

[Patriot]

...or in that case, rate of twist and sectional density. Velocity and B.C. aren't huge factors.

 

[RyanA]

Thanks Patriot, it definitely seems like something I could get endlessly carried away in. I'll have to look into those programs.

 

[Mattole]

I have heard a lot of good things about the XD, but I suggest that you consider the S&W M&P as well. It comes in 9mm, .40 and .45acp. After looking at several makers of .45 pistols including the XD I found that the S&W fit my hand better than the others and just felt more balanced. S&W was having a special promotion at the time where they offered a $50 rebate and 2 free magazines. It was a great deal and I am very happy with the pistol. In .45 it is quite friendly to shoot (even my wife, with much smaller hands, likes shooting it) and very accurate.

 

[PhotonWrangler]

Are you key holing in paper or just having accuracy issues?

I'm seeing some slight keyholing in paper targets, so I want to get a visual on when it starts to happen.

 

[Patriot]

I'm seeing some slight keyholing in paper targets, so I want to get a visual on when it starts to happen.

That would be interesting to see for sure. If you end up doing this please share a video link for us. :) As far as a cure goes, you probably already know that you'll have to increase your rate of twist (new barrel) on lower S.D. (shorter bullet). Secondarily if the bullet's surface bearing is too small and velocity too high that will also cause a failure to stabilize. I experienced this once with 110gr Hornady round nose @ 3100fps from a 1:12 twist barrel. It was a ballistic experiment to see if tumbling would occur and it did. Lastly, if the bore is worn over-sized or bullet's undersized they could also be stripping but that's a kind of fringe. Along those same lines non-jacketed pistol rounds pushed too fast can also strip and leave the muzzle unstabilized. I've seen this before with non-jacked .44 mag and .357, plus lead builds up in the bore in an atrocious manner. :sick2:

 

[PhotonWrangler]

Thanks for the information, Patriot. These were short rounds but full metal jacket. I don't recall the velocity at the moment.

If I pull off this video I will post the results!

 

[RyanA]

I had to edit some of the math from my earlier post, I thought it over and it was incorrect.