I have a M1100 Magnum a customer brought me for repair. It had a bent barrel, was missing all magazine components and customer complained it would not eject. I straightened the barrel, replaced the missing components, cleaned and re-assembled. Barrel is labeled 3 in Magnum and only has one off-set gas port. It is clear and undamaged. Gas rings are worn and pitted but not worse than I have seen. Gas seal was stretched and damaged so I replaced it. I loaded three rounds and cycled them through the action by hand and it fed, loaded, and extracted normally. Chamber is smooth and not pitted. When I test fired it, the action failed to open at all. I had to manually eject spent rounds. I test fired it with three in. buckshot and field loads. Gas seal appeared crushed.

Can anyone offer a possible cause and remedy?

Thanks,

Bob

The serial number should end in M,N or U to be a magnum action if I recall correctly. You may have a 3" barrell with one port on a standard action.

The serial no. on the receiver begins and ends with M. This one has me stumped.

Gas system usually causes these types of failures. The metal rings should be replaced first along with a new gas seal. I had a gas port broach to clear the port on the barrel. I think it was about .092 dia. , but could be larger. On the older 1100's a miss matched barrel extension would allow the locking bolt to slap to top of the receiver and slow down the action for a fail to eject the case. Cut down the action to match the barrel extension by checking using the barrel that is causing the problem. If the action bar with the plate supporting the bolt and locking block comes loose it will cause the same failure. Check to see if the silver solder has turns loose from the action bar. The plate which has the operating handle held in place is hard to tell if it has turned loose. You may need to re silver solder the block on the plate. These are some of the problems I found when working as a warranty station for Remington Arms Co. Make sure that the action is not greased heavy on the 1100's. On the Brn. A5 use lots of grease.

quote:

Originally posted by LesBrooks:
On the older 1100's a miss matched barrel extension would allow the locking bolt to slap to top of the receiver and slow down the action for a fail to eject the case. Cut down the action to match the barrel extension by checking using the barrel that is causing the problem.

Thanks for the detailed advice Les! That will definitely go in my personal gunsmithing kinks file. Can you be more specific related to the above quote? How does one exactly match the extension to the action? Does it involve altering the locking bolt engagement?

Thanks,

Bob

Take the barrel out of the receiver and look into the area in the top of the receiver for an indication of the bolt slamming into the metal causing it to be upset. The bolt needs to ride smoothly to the rear. I used a file to reduce the metal from the front of the action inside. It does not alter the bolt lock up. If the barrel and magazine tube both bent you may need to replace the magazine tube by silver soldering a new one into the receiver.

I checked the inside of the receiver and sure enough, there are several areas where metal had been upset by the locking bolt. There was also two large burrs of upset metal on the bolt side of the locking lug seat in the barrel extension. I reduced all of these to surrounding metal level. The gas rings are replaced as is the O-ring. Magazine tube is dead nutz straight.Off to the range tomorrow!

Thanks again,

Bob

Bob,

Check the locking block at the top and radius a small amount if it is sharp. Sometimes the lug is sharp enough to cause the dents. Break the edge and than a little polish on the edge will help.

I wondered about that. I will break the edge and smooth it. Thanks!

Bob

quote:

Originally posted by LesBrooks:
Bob,

Check the locking block at the top and radius a small amount if it is sharp. Sometimes the lug is sharp enough to cause the dents. Break the edge and than a little polish on the edge will help.

OK, range report. I tried firing it again after mods with 3 in 00 Buck, still no cycle. I replaced the barrel with a spare 26 in. 2 3/4 in. 12 gauge. It functioned flawlessly with 2 3/4 in., 3 1/4 dram, 1 oz. loads. So, are these "Magnum" 1100's only designed to function with labeled magnum loads? The single gas port is tiny compared to the two ports on the other barrel. It seems like it is not metering enough gas to work the action even with high brass 3's.

Bobster-these guns can be finicky about the amount of gas required. Have you run a bit into the port to be sure it's clean. Just a bit of carbon or trash will hang it up but at this point it obviously isn't getting enough gas to operate. Wish I had the gun in hand, this is like a doctors diagnosis over the internet.

I ran a small drill bit thru it and there was no indication of obstruction. It is perfedtly round with no signs of buggering. What gets me is the action doesn't even unlock at all. Not even a partial cycle. Yes, the problem is obviously with the Magnum barrel. I just noticed a very shallow semi-ring in the bore at about 2 o,clock near the port location. I wish I were close enough to you to let you look at it.

Edit: Problem solved! Turns out the 3 in Buck rounds I had weren't magnum enough. This gun apparently needs 3 in shells labeled Magnum specifically. I think 3 1/2 drams of powder is the tipping point.

Thanks for the help.

Bob