FTE - Carlson Barrel - 870

[TYFOON]

So this 870 is the one that has been sitting for 20 years.

First trip to the woods was with a new Carlson barrel installed.

PMC 2.75" 00. First shell goes boom, slide comes back, no empty shell.

The afternoon proceeded this way. I could slam the slide forward and sometimes then be able to extract, but sometimes not. Never would the fired shell come out first try. Very disheartening for a 870 fan.

I took a good look at the extractor's contact on the brass as it comes out of battery. What I discovered was that this Carlson barrel did not leave enough space between the extractor and the shell when in the chamber.
When chambering a shell the Carlson would deflect the extractor up as the extractor slid over the lip on the brass, then on the way back out there was just no brass for the extractor to grab.

I took a look at my Remington barrels when I got home and sure enough. There is a notch machined out on the Remington’s to allow the extractor bite on the shell. I took out my trusty Dremel and notched my Carlson. Any one else experience this?

I have not shot the gun since the mod so I hope this cures the FTE issue because it's nauseating not having faith in your Shotty.


Before:



After:

[Synchronizor]

My barrels are all Remingtons, but they don't have the fully-cut-out notch like the one you cut into your barrel. The notch is meant to give the extractor a place to go when the bolt is locked into battery, with the shell rim sticking up at the end to be grabbed during ejection. It's possible the notch wasn't quite machined right, but it is supposed to be that shape.

I have the card out of my camera to edit some video right now, but I can upload images later if you want to see them.

The first thing I would have looked at would be your extractor, and the extractor spring & plunger inside the bolt. If this gun has been sitting for 20 years with gunk inside that little space, it may be affecting the performance of the extractor, which could contribute to the problem. Some budget-level 870s (especially newer ones) also have extractors with looser manufacturing tolerances. They usually work well enough for a gun at that price point, but once in a while the part will be far enough out of spec to cause problems.

After checking and cleaning the extractor, if the notch still seemed to be affecting extraction, you probably should have contacted the manufacturer first. I've heard a lot of good things about Carlson's barrels, and haven't heard of anyone else with FTEs that couldn't be blamed on the extractor.

If you did decide to cut on it yourself, it would have been better for you to take it down slowly while keeping the same angle, checking for function as you went. By completely notching the barrel like you did, you've weakened its structure in a critical location and decreased case support for the shell.

[Kentactic]

The before picture is how mine is. atleast in general apearance. Its an angled cut so when theres no round in battery the extractor has a ramp to slide up on.

[TYFOON]

Thanks for the posts guys.

I see your points but my trim work can't really be appreciated the way the photos above look.

The extractor mating area on the barrel has a flat surface the same shape as the extractor, it is not round like the photo looks. I copied it from the Remington and I got to say, they are pretty darn close:) The extrator still rides up the ramp into battery any pushes out beyond flush with the bolt just a hair, just the way it should. The weakening of the support for the case I am not really concerned about as it now sits more like the Remington barrel. Besided, I just don't see how Carlson gets these to work the way this came I really don't there was nothing to "extract" upon at all.

I inspected the extractor as best I can, it feels good, the spring feels good. I can press it out and let go and it snaps back into place, no binding, smooth as butter. As a note, the lower corner of the hook does have slight rounding as to ride over the shell edge but it looks factory to me, the gun has such a low round count, I think this is suppose to be this way.

I took it back out and put some different shells through it (Federal Truball slugs 2.75", more PMC, and some Winchester 2.75 #8, #8 did best extracting).

It was better at first but ended up it was happening nearly every other shells with the PMC and Federal.

I am just mistified how this would be happening when it all looks, feels, and cycles so clean with unfired shells. These things are not that precision, things should really work, no matter what.

Thoughts?

[Carlo1137]

Thanks for the posts guys.

I see your points but my trim work can't really be appreciated the way the photos above look.

The extractor mating area on the barrel has a flat surface the same shape as the extractor, it is not round like the photo looks. I copied it from the Remington and I got to say, they are pretty darn close:) The extrator still rides up the ramp into battery any pushes out beyond flush with the bolt just a hair, just the way it should. The weakening of the support for the case I am not really concerned about as it now sits more like the Remington barrel. Besided, I just don't see how Carlson gets these to work the way this came I really don't there was nothing to "extract" upon at all.

I inspected the extractor as best I can, it feels good, the spring feels good. I can press it out and let go and it snaps back into place, no binding, smooth as butter. As a note, the lower corner of the hook does have slight rounding as to ride over the shell edge but it looks factory to me, the gun has such a low round count, I think this is suppose to be this way.

I took it back out and put some different shells through it (Federal Truball slugs 2.75", more PMC, and some Winchester 2.75 #8, #8 did best extracting).

It was better at first but ended up it was happening nearly every other shells with the PMC and Federal.

I am just mistified how this would be happening when it all looks, feels, and cycles so clean with unfired shells. These things are not that precision, things should really work, no matter what.

Thoughts?

Did you try polishing the barrel like one one on the video on the site?

[TYFOON]

I Just did now. This is getting on my nerves. Why can't all things be AK47's?

[Synchronizor]

Why can't all things be AK47's?

No such thing as a free lunch. The low price and abuse capacity of the AK-derivative firearms comes at the expense of durability, system life, precision, and versatility.

I doubt polishing the barrel would have helped your issue. If shells hanging up in the chamber was your only problem, the bolt would just stick closed.

Can you post a close-up picture of your extractor? It really sounds to me like at least part of your issue is caused by the extractor not grabbing the shell rim properly.

You mentioned you had other 870 barrels. I would throw one of those on the problem gun, and see if the issue persists.

[TYFOON]

Here are some tea leaves:)



Sorry for the poor res.

[JSwenson]

Tyfoon, I was having extraction problems with a new Mossberg 930, and after checking everything I could think of, I noticed that the Mossberg barrel had the same design you describe. The extractor notch does not allow the extractor to make full contact with the rim of the shell. I thought this was a flaw, but I drug out my 870 and a Winchester, and they all had that same design. I do not understand why they are all that way, because it sure keeps the extractor from getting a full bite on the rim. I had considered notching mine like you did, but I wanted to wait and get some expert opinions. Keep us posted. I also noticed on one of my barrels that the ramp that extractor rides up on was rough - I thought that might cause premature wear of the extractor.

[TYFOON]

We'll do.

Today I:

Ordered a new extractor Brownell's for $15.00 and extractor spring for $4.99.

Stripped, cleaned, and lubed bolt and existing extractor and extractor spring.

Loaded up some steel wool in the drill lubed with WD40 and polished the chamber.

I sanded and polished the barrel surfaces exiting the chamber with polishing compound on a felt wheel and drill.

Everything is greasy smooth right now. I may not shoot it before the new extractor gets here but I will report back if I do.