A few years ago I picked up a model 340 in 22 Hornet at a small gun show.Was told the barrel was shot out and it was $150 price tag.Took me 2 weeks to clean out the barrel to show a perfect shiny bore.One item I found peculiar was the rear sight that has a thumb screw adjustment for height.I was able to find an original scope mount and El Paso Weaver to fit it.
Was wonder How does one find the differences between the 340,B,E series and years of production?

Should be either a date code (1 or 2 numbers in an oval stamp followed by a letter), or a serial number starting with a letter. We can date it for you with either of those.

Nice grab, by the way. I love Hornets.

The difference in the entire 325/340/342/840 family are mostly cosmetic. They are good, entry level, rifles, but due to their generally poor triggers, less accurate than they might me. I used to sell the 30-30s by the Suburban load to a pawn shop in WI, but don't see them in the $75 to $125 range much anymore.

I looked at the rifle and there are two ovals just ahead of the barrel nut.One has SP in it and the other is 38 or 8E depending on which way I look at it.The rear sight is a Dockendorff.It also has unusual sling swivels that will detach from the stud with a thumb screw.Never seen anything like it myself.

8E would be 1953, the 342 first came out in 1950.

Do yourself (and everyone around you) a favor and make sure you take the action out of the stock and make sure the area around the trigger and safety is clean. Many of them have a build-up of factory grease that can cause the rifle to accidentally fire.

I have a 340 in 30-30 that would consistently drop the hammer when the safety was taken off because of this. This is a common problem with these rifles.

I will repost a posting from Randy S, as his info is right on

"Time for the annual lecture on 325/340 safety.

To prevent an accidental discharge, remove the action from the stock, throughly strip the grease from the trigger mechanism with GunScrubber or brake cleaner, oil lightly, and replace action.

The trigger mechanism is completely enclosed in a stamped steel housing which is integral to the workings of the trigger. The housing was packed with grease at the factory. 60 years later, in most cases that grease now has the consistency of taffy.

The bolt can also be packed with grease, so clean and oil that, too.

A friend and I go to the woods to target practice with my grandfather's 325A 30/30. Gramps bought it new from a hardware store, and shot at most a box of shells. I load it, hand it to my friend, who shoulders the rifle, aims, and pulls the trigger. Rifle does not fire. Oops, he did not take the safety off.

He brought the rifle to port arms, (bbl still pointed down range), rotated the safety rocker/lever to "Fire", and the rifle discharged. After unloading, I was able to reproduce the AD every time. After investigating, I could see that pulling the trigger with safety on "Safe" prevented the striker from dropping, but the taffy/grease held the sear back. When safety was set to "Fire", the complex trigger (sear) was back enough to release striker.

After cleaning trigger mechanism and bolt, and proper light oiling, the safety works as expected; no fire on "Safe", and rotating safety to "Fire" does not drop striker. My 340D had the taffy/grease, but did not reproduce the AD conditions. Maybe it was due to difference in design, or quantity of grease.

Thanks to all for the info.
Yes,I have taken the action out and cleaned thoroughly.

Thanks cv540.I will take the rifle apart to check for old grease in the trigger/safety area.Better to err on the side of caution.

The rifle is a bulky sort with its oversize walnut stock and all,but its a decent rifle for the money I have into it and I like it.I'm partial to old time workmanship.The little Hornet is fun and cheap to shoot.(I reload)

Yeah, If I found one in 22 hornet, I would jump on it. Saw one on here a while back in 222 which tempted me.

I use my .30-30 which has a peep sight as a still hunting whitetail rifle if it is snowing hard. Was going to use it as a youth rifle to loan to nieces and nephews but the AD issue kind of freaked me out and I don't really want anyone else using it.

Since I cleaned it good, I haven't been able to replicate the issue, but it is always kind of in the back of my mind if you know what I mean.

The requirement for a side-mounted scope, split rear bridge, and single locking lug have always turned me off toward the 340 family of rifles.

The rifle is a bulky sort with its oversize walnut stock and all,but its a decent rifle for the money I have into it and I like it.I'm partial to old time workmanship.The little Hornet is fun and cheap to shoot.(I reload) - I have often thought what sleek little rifle they would be if all the extra wood was removed. As is, they remind me of the old Mossberg bolt action shotguns.