This data is collected from my Kimber TLE/RLII 5” 1911
Factory rounds are Winchester White box 230gr. Looks like my 200gr/4.5gr Clays is holding up to Major Power Factor. So I’ll stick with that formula. If I need to switch to 230gr, then I’ll use a 3.6 gr charge of Clays.
Here’s the data that’s shot out of a Kimber Eclipse Pro II 4” 1911
As you can see, the difference in Power Factor is drastic by just dropping one inch in barrel length. There isn’t enough barrel for the powder to burn completely and for the bullet to achieve it’s maximum potential. The 200/4.5 load suffered badly in a 4”. If I’m seriously going to shoot the 4” with my reloads, it’ll have to be with at least a 4.7 or 4.8 gr charge. For now, it’s my backup gun for IDPA and will be a carry gun running the Ranger-T +Ps.
After hearing about this from my buddy Victor, I decided to give it a shot and try to make this hack which is known to reduce felt recoil dramatically. Here’s the procedure : http://elmtreeforge.blogspot.com/2007/03/1911-firing-pin-stop-modification.html and the sticky thread on 1911 pistol forums : http://forum.m1911.org/showthread.php?t=13060&page=1
The hack is to basically use an oversized firing pin stop, (you can order this from EGW) and file a very small 45 degree bevel instead of a huge slope.
the one in the middle is the stock Kimber Firing stop(this is a series 80 version). The one on the right is my failed attempt at trying to get a straight parallel bevel. The one on the left is a Series 70 firing stop (which works on my Kimber) that I managed to get right.
The idea is that by having a small bevel, it contacts the hammer and creates extra tension so that the slide loses more energy as it moves back from recoil, thus reducing felt recoil. I have to try this out tomorrow to see if it works. If it does, I’m gonna shoot my WA State IDPA Championships with this installed 🙂
Went out to the range recently and tried to chrono some 230gr bullets I loaded. I actually tried loading 5 different grains of Clays powder using 230gr Bear Creek Moly bullets. 3.7gr, 3.8gr, 3.9gr, 4.0gr and 4.1. The recommended maximum load is 4.0grs when using 230gr. My goal was to get as close to 170 power factor as much as possible. The formula is (Bullet Grain x FPS) / 1000.
I started with the lowest of course 3.7gr, but before I started, a buddy of mine, Tavis, told me that he shot 3.5gr out of his 5” Kimber and got a 172PF rating. I guess I should have downloaded my rounds more, but here goes:
|3.7 gr||3.8 gr|
Tavis was right. It looks like I have to load down to 3.5 or 3.6 gr and chrono the rounds again next week.
I’ve been playing with compensators recently and decided to see if I can fit one on my Kimber without having to change barrels or gunsmithing. Found a EFK FireDragon 1911 Bushing Compensator which is awesome because you can just swap the bushing in and out “relatively” easily. It retails for $69.95 and requires some fitting.
Here’s how it looks shipped from Fire Dragon
as you can see, the throat is a little large so you can customize and fit it to your slide.
Out comes the Dremel and a sanding tool :
after 10minutes of sanding and refitting:
All dressed up tacticool-style. Haven’t had a chance to shoot it yet but will get to it.
It’s been a while since I went shooting so I didn’t do so well, just looks fast on video. Raw time was pretty good though, but had too many points down. Need to work on my accuracy & reloading next!