Writer wants to get it right

A little bit of knowledge can be a dangerous thing. I am writing a story in which one of the characters knows far more about firearms than I do. I can now confidently say SIG P226 X-FIVE Tactical chambered in .40SW with a 14-round magazine and know what I'm talking about (even if I can't remember right now if the tactical is SAO). I'm learning an awful lot about ammunition, more than I think I need to know, but there's a lot.

So I think I'm doing better than a lot of writers so far. The thing is, this character really, really, knows guns. I think I have avoided embarrassing myself except for one passage, which I would appreciate having a group like this vet. I'm sure there are a host of other questions that you could help me with as well.

Would this be an appropriate place to post questions like that, or is there another place you could recommend? I know that the gun community (like any other technical group) hates it when fiction has stupid, avoidable errors and misconceptions.

I promise that when the movie poster comes out, the babe's finger will be safely off the trigger.

EDITED TO ADD: And now I see that the X-FIVE Tactical only comes in 9mm...

Thanks!

I must confess that there is one scene in which the bullet ballet will strain credibility, but I'm trying to make sure that it is the human who is exceptional, working within reasonable parameters (no outrunning AK 47's in a hallway, magazines with finite rounds and barrels that overheat, magical suppressors, and so forth).

So here's the bit where technical knowledge sits right on the surface; I'm using this scene to help establish Kate's character -- socially inept, technically extremely competent. She is, above all, precise. She has fired Schmidt's gun in the past, and is now returning it to him.

There are three paragraphs in the following passage that (obviously) are exceeding my technical knowledge. You'll know them when you see them. If you could tear them apart now, that will save me embarrassment later. I put the stuff here fully expecting to be criticized -- that's the point of this exercise -- so don't worry about hurting my feelings.

I have avoided specifying Schmidt's gun; it could be anything a European law enforcement agency might use, whatever provides the best fodder for this conversation.

(Please remember that this is a copyrighted excerpt from a larger work.)

***
KATE
I brought your gun back.

Kate reaches into her bag and pulls out Schmidt’s pistol, careful to hold it in a non-threatening fashion, and sets it on the table between them. She reaches back and produces the magazine and sets it next to the gun.

KATE
I, uh, I tuned it up a bit for you.

Schmidt picks up the gun and looks at it curiously.

KATE
I adjusted the double action so the pull on your first shot is more consistent, and I reduced the overtravel, but not by much. Most of the parts were in pretty good shape, but the cartridges you had didn’t give me very consistent results. Sometimes it’s hard to predict how a cartridge will work with the internal ballistics of a particular gun.

SCHMIDT
Huh.

KATE
I tried out a few different rounds. I got good results with Federal JHP. Kind of surprising, really, but you should try those. The Cor-Bon +P worked pretty well too and it’s a good stopper but if you switch make sure you practice a lot or you’ll shoot high at first. And, uh, for special occasions...

Kate reaches once more into her shopping bag and produces a box of cartridges. Her hand shakes just a bit as she sets them on the table, betraying a shy nervousness.

KATE
I made you these.

Schmidt looks at the box, nonplussed. Kate sees his reaction and speaks faster, her embarrassment growing.

KATE
The first ones I made the propellant burned a little too fast for a 115 grain bullet so I switched to AA-7 and when I used the PMC case I started getting some good groups. It might be a little more energetic than you’re used to, more like a +P, but... uh...

Schmidt is watching her, bemused. She looks down at her hands

KATE
That’s weird, isn’t it?

****

One specific question -- when europeans talk guns, do they still use measures like grains or would grams be used instead?

Is adjusting someone else's trigger a no-no?

Thanks once again for your help. In the mind-bogglingly unlikely chance that this goes somewhere, I really want the gun parts to be accurate in a story that has lots of guns in it.

What other options are there that she could do to improve his gun's performance that would not cause those concerns? It is safe to assume that while she may not be a gunsmith, she is very competent in firearm maintenance, and will never be far from a full set of tools.

Yes, we will see on a later 'special occasion' that Schmidt needs to practice a little more. Of course, when you really realize that, it's too late...

The pistol can be specified to be anything a european cop might carry; whatever gives good options for tweaking. I think I can take it from there with your above suggestions -- thanks!

Any thoughts on her making cartridges tuned to his gun or any of the other stuff? Presumably changing the barrel would change the pressure curve, which gives me a nice closure with changing propellants. Or am I talking out my ass now? Sometimes it's hard to tell.