Ok so I loaded up some of the new 180 TCFP I recieved from Falcon yesterday. Started with 4.9 of 231 and seated them to 1.125. They failed ty the "plunk" test and would not fully seat in the chamber. I had to go down to 1.141 to get them to seat fully in the chamber. What will that do to my pressures? They are .628 in length and .401 diameter. My standard 180 are .638 in length so I am hoping all should be fine. Can anyone please help with a pressure calc or insight? Thanks
Seating depth issue .40S&W
- Thread starter recon14
- Start date
ScottRiqui
New member
I think one or both of your OAL measurements is a typo, because I don't see how you can go "down" from 1.125" to 1.141".
jersurf101
New member
My standard for 155 grn XTP's is 1.125 but they will feed well at 1.130 and not much past there.
g.willikers
New member
Without a way to measure, it's a guess.
At least get a chronograph to show the velocities.
It's not a fool proof way to measure pressure, but it's a lot better than guesstimating.
At least get a chronograph to show the velocities.
It's not a fool proof way to measure pressure, but it's a lot better than guesstimating.
I went through the same thing with my XD. It seems to have a short throat, or whatever. Anyway, those style bullets I had to seat really deep to get them to chamber.
I ran a test ( different gun that doesnt care ) with W231 seating at 1.125, all the way down to 1.085, and recorded the results from my chrono.
When I get home tonight I can post the results, if that helps you.
JIM
I ran a test ( different gun that doesnt care ) with W231 seating at 1.125, all the way down to 1.085, and recorded the results from my chrono.
When I get home tonight I can post the results, if that helps you.
JIM
Voyager2011
New member
Just spoke with a competition shooter friend who shoots exclusively the 40-180 from Falcon Bullet Company. He said a good start is 1.126 with a .418 crimp. Go slow and watch the pressure curve. That was for his XDM. Of course, his comp gun is different since it is modded. Hope this helps.
Ok heres what I have. For the test, I used a .40 carbine, since it will shoot anything i have ever put in it. Should give you an idea of how oal affects velocity / pressure
180 Gr truncated cone Flat point
W231 powder
4.5 @ 1.120 AVG 1036
4.0 @ 1.105 AVG 952
4.0 @ 1.090 AVG 950
Then, I was satisfied that I wasnt in an overpressure situation, I shot the last load from my XD 4"
AVG was 853
JIM
180 Gr truncated cone Flat point
W231 powder
4.5 @ 1.120 AVG 1036
4.0 @ 1.105 AVG 952
4.0 @ 1.090 AVG 950
Then, I was satisfied that I wasnt in an overpressure situation, I shot the last load from my XD 4"
AVG was 853
JIM
brokenanew
New member
Well...youll know when you try 
. It depends on your powder load of course. 1/100ths of seating depth can make for some moderate changes in pressure especially with the 180gr. Lyman says a 180 can be seated at 1.15. I think youll be ok but be sure your not in the max range of your load. As always be safe, smart and just work up your load. The .40 can get hairy with pressures when u start messing with seating depths to much.
If your running max or close to max at 1.25. You may have to back off a tad if your going to 1.14. The .40 is pretty high pressure, so yes I would think about readjusting powder load
. It depends on your powder load of course. 1/100ths of seating depth can make for some moderate changes in pressure especially with the 180gr. Lyman says a 180 can be seated at 1.15. I think youll be ok but be sure your not in the max range of your load. As always be safe, smart and just work up your load. The .40 can get hairy with pressures when u start messing with seating depths to much. If your running max or close to max at 1.25. You may have to back off a tad if your going to 1.14. The .40 is pretty high pressure, so yes I would think about readjusting powder load