different problems on a .40 S&W.....kinda long but might help another.

[onelight]

I have run red dot in my .40 with a 180 fp. It cycled well but I have not done any serious accuracy testing with it.
The 2002 alliant reloading guide shows a max of 5 grains with 180 jhp
I have tried both 4.1 and 4.5 with 180 hi-tek coated both cycled my XDM 3.8 and 5.25

[Todd N.]

Just out of curiosity, what pistol are you shooting this from?

Also, how did you measure your chamber?

[mozeppa]

Just out of curiosity, what pistol are you shooting this from?

Also, how did you measure your chamber?

this pistol...STI Trojan

and i used a set of precision ground pins to measure at the case mouth and at the back of the chamber where the case head touches.

[Todd N.]

Okay, here are my opinions based on your statements and no physical exam of your gun:

1. SAAMI specs have absolutely no bearing on how your chamber is cut. They are a recommendation of parameters that are not binding on gun or ammo manufacturers. This is further proven by understanding that European countries ascribe to a different standard - C.I.P. (Commission internationale permanente pour l’épreuve des armes à feu portatives – Permanent International Commission for the Proof of Small Arms)- which IS binding and often has different dimensions for the same cartridges we use here. Having said that, one must understand that that it is a given that there will be variations in chambers between different manufacturers, variations in reamer dimensions, variation in reamers in a single manufacturer based on wear, etc... Chamber and barrel dimensions are a "+/-" situation.

2. There is nothing wrong with your AA#5 load. Again, without physically seeing anything, I believe you would benefit from more crimp. As I'm sure you know, many powders- not cartridges- need a heavier than expected crimp to build start pressure for a clean , complete burn. I suspect this is not your situation though it might benefit you to try it. This also ties in to the "pop" you mentioned in Post # 18.

3. You state that your bullets are powder coated. With what product? Not all powder coatings are created equal. Based on your statements alone, I would want to explore the possibility of powder coating failure and buil-up in the chamber. Is the coating one you buy and apply yourself or do you buy the bullets coated? Are the bullets sized before or after sizing? Like others here, I am curious about bullet and case dimension "as loaded" relative to your actual chamber and bore dimensions. Remember, every barrel is a unique specimen with it's own quirks.

4. You gave chamber dimensions as measured with pin gauges. Did you make a Cerrosafe cast of the chamber? I am not a gunsmith, I am a Material Destruction and Failure Analysis Engineer. My employer has analyzed over 400 firearms in its history, and it is a standard practice for us to do this both for our analysis and at the request of our customers. If you haven't done so, you might consider using this product to get more information about your chamber.

I know how frustrating this can be. I also know what a fun challenge it is to make a gun work properly. I think you are the type who wants to find out how to get something to work as well as why it didn't work with other components. If you want a simple answer to whether or not dirty-burning powder is your culprit, try loading up some of your bullets with Unique. A low charge of Unique will soot you up like few other powders! That is one that could verify or rule out powder as your gremlin. Again, keep all other components the same, just change your powder.

This has been interesting to follow. Please continue to update us.

[mozeppa]

todd...i answered you in red via your quote ...so i wouldn't leave anything out.
i shot bullseye yesterday in it and it functioned much better...still a little dirty but not like AA#5.

not that i'm trying to get out of actually cleaning my gun or anything like that ...but..i do know that i have picked up "one time shot"
factory brass off the range floor (not mine!) and the insides of the cases were nearly as bright and shiny as the outside. ???
why can't this be duplicated?

that is as clean a burn as i have ever seen! no evidence of soot, just heat.

Okay, here are my opinions based on your statements and no physical exam of your gun:

1. SAAMI specs have absolutely no bearing on how your chamber is cut. They are a recommendation of parameters that are not binding on gun or ammo manufacturers. This is further proven by understanding that European countries ascribe to a different standard - C.I.P. (Commission internationale permanente pour l’épreuve des armes à feu portatives – Permanent International Commission for the Proof of Small Arms)- which IS binding and often has different dimensions for the same cartridges we use here. Having said that, one must understand that that it is a given that there will be variations in chambers between different manufacturers, variations in reamer dimensions, variation in reamers in a single manufacturer based on wear, etc... Chamber and barrel dimensions are a "+/-" situation.

2. There is nothing wrong with your AA#5 load. Again, without physically seeing anything, I believe you would benefit from more crimp.(if i use any more crimp ...it'll look like a roll crimp) As I'm sure you know, many powders- not cartridges- need a heavier than expected crimp to build start pressure for a clean , complete burn. I suspect this is not your situation though it might benefit you to try it. This also ties in to the "pop" you mentioned in Post # 18.

3. You state that your bullets are powder coated. With what product? Not all powder coatings are created equal.(i use smokes from on this site to powder coat using a espc gun to apply it, the coat is very uniform ...not globby.) Based on your statements alone, I would want to explore the possibility of powder coating failure and built-up in the chamber.(nope nothing but soot in the chamber nothing colored or sticky , just soot.) Is the coating one you buy and apply yourself or do you buy the bullets coated? Are the bullets sized before or after sizing? always sized to .4015 AFTER powder coatingLike others here, I am curious about bullet and case dimension "as loaded" relative to your actual chamber and bore dimensions.the chambers and cartridges in my drawings are of the gun in question with the measurements shown on the drawings Remember, every barrel is a unique specimen with it's own quirks.

4. You gave chamber dimensions as measured with pin gauges. Did you make a Cerrosafe cast of the chamber? yes i have and it bears out what i recorded on the drawings I am not a gunsmith, I am a Material Destruction and Failure Analysis Engineer. My employer has analyzed over 400 firearms in its history, and it is a standard practice for us to do this both for our analysis and at the request of our customers. If you haven't done so, you might consider using this product to get more information about your chamber.

I know how frustrating this can be. I also know what a fun challenge it is to make a gun work properly. I think you are the type who wants to find out how to get something to work as well as why it didn't work with other components. If you want a simple answer to whether or not dirty-burning powder is your culprit, try loading up some of your bullets with Unique. A low charge of Unique will soot you up like few other powders! That is one that could verify or rule out powder as your gremlin. Again, keep all other components the same, just change your powder.

This has been interesting to follow. Please continue to update us.