[PinnedAndRecessed]

I went to the range today and fired my Mark4/Series 70 Colt. Some of the cases did not fully eject, but turned a full 180 degrees in the ejection port and jammed.

The gun was sufficiently oiled prior to firing. The slide was tightened to the frame by Clark Custom Guns. It has an aftermarket satin nickel finish by Trapper Guns. It also has a Wilson recoil buffer and Wolfe 18 pound spring.

The load is a 200 grain SWC plated bullet with 6.3 grains Unique.

I experienced no such problem when firing PMC hardball ammo.

Since the 6.3 grains Unique is not far from maximum recommended by some manuals, I'm thinking maybe just try a weaker spring.

What say ye?

Thanx in advance.

[1911Tuner]

Pinned&Recessed asked:

>What say ye?<
***************

Tunefucious say:

Honorable slide is oversprung. Try 16 pound Wolff spring for happy gun and joyful shooter. If honorable gun is tight, maybe 14-pound spring would bring harmony.

May the force be witcha.

[Gunsnrovers]

LOL.

All 1911 Q&A's should be answered by "Tunefucious".

ps - It does sound oversprung.

[PinnedAndRecessed]

How bout dat?! I was oversprung and didn't even know there was such a thing.

Shall take your advice and many thanx, grasshoppa.

Stay tuned for part 2. (To see how she works.)

:)

[stans]

Odds are 18 pounds is too much spring, 16 is more like it. I know it was all the rage to put in 18, 18.5, and even 20 pound springs, but this induces ejection problems unless you are shooting +P, +P+, or OMG! ammo.

[1911Tuner]

To restate a previous point on spring rates and loads...

Rule of thumb: Spring loads need to go up as bullet WEIGHT goes up, rather than pressure and/or velocity. The recoil spring has almost nothing to do with containing pressures. Pressures are contained by the unlock timing of the gun, which occurs in the first .100 inch or so of slide travel, where the recoil spring has very little effect. If you want to delay the unlock timing and give the pressure a little more time to fall off before barrel unlocking begins...go up on the MAINSPRING load and use a small radius on the firing pin stop to further delay the onset of barrel and slide unlock timing.

Velocity plays a role in selecting a recoil spring...but the bullet weight/mass
has the greater influence in the recoil impulse.