Different 9mm- different ejection

[gifbohane]

Today I used my S&W 9mm instead of my CZ 75B. First time in a year (or so). Made a very interesting and non scientific discovery.

The CZ always ejected about 5 or 6 feet and the S&W maybe 2 feet with the same loads.

Thoughts? Maybe the tight CZ chamber?

 

[BiknSwans]

Maybe too strong a recoil spring in the M&P. I use a 13 pound spring in mine and get about 5 feet with a new spring.

 

[gunzby]

Most likely a heavier recoil spring. I have shot a shield in a while, but I do remember it having a decent spring on it. My CZ p07 definitely has a lighter spring.

 

[gifbohane]

So the lighter spring tosses the empties further...... CZ is stock...MP is modified.

 

[Zerodefect]

Totally different pistol. But that's a possibility.

My larger frame Glocks dribble out cases in a perfect rainbow. My 1911's fling them straight.

 

[SingleActionAndrew]

So the lighter spring tosses the empties further...... CZ is stock...MP is modified.

To Zero's point above, that's generally true for the same pistol. Not necessarily pistol to pistol. Even 1911 to 1911 based on barrel fitment etc. But in the same pistol, yes lighter recoil spring for the same loading will throw brass further. Generally I desire the heaviest spring that the load reliably cycle.

 

[gifbohane]

Thanks to all of you for the info.

 

[Spare Parts]

My G17 ejects right, straight back, or left, depending on the powder load. Discovered while working through a ladder.

Theory: Lighter powder load = less maximum compression on the recoil spring = ejects-not-so-much-to-the-right.

 

[rfwobbly]

1. The difference between the guns will show up in what direction the ejector throws the case. Some auto pistols throw the case out to the right, while others might put them straight back over your head.

2. The difference in "springing" between guns will show up in the distance the case is thrown when using the same ammo. You will not simply be able to compare spring strengths based on their book value. Both guns may have "18 lb springs", but one may be installed with slightly more compression, which can effect how the spring behaves. Also CZ's rating system may vary from S&W's. There are simply too many variables between mounting, rating, conversion from metric, flat vs. round wire, twisted wire construction, or dual rate springs, etc.

Hope this helps.

 

[jmorris]

So the lighter spring tosses the empties further

An increase in slide velocity would equate into an increase in velocity of the case hitting the ejector.

FWIW there are some firearms that are really close like the Mini 14 with its spring loaded ejector and the early Ranch rifles with their mechanical ejector. Looking at them the only difference that stood out were the scope ring cut outs on the Ranch. Once you shot them, you immediately knew there was another difference as one put a pile of brass beside you and the other threw them into the next county.