Remington 870 Tactical Ejection Port Dimension

[unclerandy]

https://www.rem870.com/2017/07/21/3-...n-870-chamber/

99% this is your problem. The last few years the bean counters were trying to save money and chambers were not cleaned up/ polished like they needed to be.
If you are local to me I have a 12ga honer and the oil 5 mins on a drill and it will be done.
Ill add my ejection port measurement here shortly.

Chamber was already honed and not an issue.

[BajaJames83]

So what exactly is your gun doing ?
We cant help you without knowing what is happening

[W.R.Buchanan]

So when you rack the slide do you just open it slowly or positively rack it hitting the back stop of the slide which should positively eject the spent rounds?

Where exactly do the hulls hang up, and do they do it the same way everytime? Pics please.

People tend to baby pump guns thinking they shouldn't be racked with authority. This is not the way to go about it. You need to positively rack the slide running it to the rear with authority and then forward the same way. Otherwise you run the risk of "Short Stroking" the gun which can result in malfunctions like you describe.

The reason why people are not responding the way you want, is because this malfunction makes no sense. The ejection port on your gun is exactly the same as every other 870 of the same model, It literally can't be different or it would have been scrapped.

If the Extractor is pulling the spent hulls from the chamber then it is fine, and if the Ejector sticks up far enough to hit the rim of the hull then it should kick the round out. If it doesn't then that could be your problem.

Randy

[NapalmCheese]

Mine, from 2008 or so, measures 2.97.

Edit to add: This is an 870 Express security gun with a factory mag extension. I've never fired a 3 inch shell through it so no info there. I can't recall having any problems with 2-3/4 inch ammo.

[JagerDog]

Did you determine which receiver you have? Std, mag, super mag.

[unclerandy]

So when you rack the slide do you just open it slowly or positively rack it hitting the back stop of the slide which should positively eject the spent rounds?

Where exactly do the hulls hang up, and do they do it the same way everytime? Pics please.

People tend to baby pump guns thinking they shouldn't be racked with authority. This is not the way to go about it. You need to positively rack the slide running it to the rear with authority and then forward the same way. Otherwise you run the risk of "Short Stroking" the gun which can result in malfunctions like you describe.

The reason why people are not responding the way you want, is because this malfunction makes no sense. The ejection port on your gun is exactly the same as every other 870 of the same model, It literally can't be different or it would have been scrapped.

If the Extractor is pulling the spent hulls from the chamber then it is fine, and if the Ejector sticks up far enough to hit the rim of the hull then it should kick the round out. If it doesn't then that could be your problem.

Randy

You've made an incorrect assumption that a receiver can't make it off the line with out of spec dimensions. Military and LE have been cutting the rear of the ejection port for a really long time to improve ejection and more importantly to see that the empty has come out. I just wanted some reference examples of the port opening. I appreciate the input but reference measurements is all I wanted and asked for.

[W.R.Buchanan]

Pictures of the hang ups please !.

Incidentally I own a machine shop. 870 Receivers are made in a machine shop on CNC machines which do exactly the same thing everytime. Minor variations in dimensions will happen from time to time, but we are talking about a few thousandths of a inch due to worn cutters, none of which will cause your problem. Also since these parts are sold to the Govt as well as civilians the parts are rigorously inspected to ISO 9001 standards and if one part is out of spec the whole run gets scrapped. Needless to say they watch them pretty closely.

Like I said we need to see pics of how the hulls hang up so we can be of some meaningful assistance.

Randy

[200Apples]

For reference my 870 super mag i just measured the ejection port at 3.48 my 870 express came in at 2.98. My father in laws wingmaster came in at 2.72.

Just measured two 1980 870 Wingmasters. Both e-ports measured like your Express at 2.980".

[FLIGHT762]

2.95" & 2.97" on two 870's "Magnum" receivers from 1980-1990 vintage.

[SoftHeart]

As far as a positive/firm/forceful rack all the way back/then forward, the 870 likes/wants to know whose "Boss".

[W.R.Buchanan]

Pics please?

Randy

[W.R.Buchanan]

One week later,,,, You'll note that we never got pics of the jammed gun.

We got trolled.

Randy