Plainfield carbine, ammo feed problems

[Fallowt]

Hello, someone on the Firingline forums recommended that I post my question here. I recently bought a Plainfield M1 carbine that seemed in good shape. I was hoping to use it as a handy home defense gun. Most literature recommends using either a hollow point or soft point ammo for best effect. With the current ammo shortage, I invested in 40 rounds of Corbon DPX 100 grain JHP. It won't feed, it's not even CLOSE! The tip of the bullet just hits the lower barrel edge and stops. And this is not like it's just a little off, I mean it looks like even FMJ's wouldn't feed. Of course, I have no FMJ's to try, because they are all on backorder. I tried it with multiple magazines, no difference. I see that this rifle has a split feed ramp, right and left sides, with well over 1/8" of space between the top of the feed ramp and the barrel lip. I've never seen a firearm with a gap like that.
There was NO WAY this round was going to chamber because the front of the bullet was just stopped dead about 2mm low of the lip of the barrel. There isn't any machining on the lower barrel edge to help feeding. It's just rounded a bit all around. I've polished a few feed ramps and barrels on other guns to help feeding problems, but I think this problem is WAY beyond the few thousandth's of an inch that can be resolved by that. It seems to me that (mainly) the feed ramp doesn't go high enough and/or extend far enough forward to meet the lower lip of the barrel, or the barrel is not seated far enough into the receiver.
I'd appreciate any advice on this rifle and ammo. It's not much good to me if it won't feed decent (or any!) ammo.

[landtrain]

It's time for your gunsmith to get involved. Sounds like some one has installed a new/replacement barrel and to get the recoil slide to mate up with the barrel left the barrel out of alignment with the receiver. Perhaps as much as one or more turns. To fix might be more expensive than to replace. IJ Carbines run around $3 to 450.

[kcw]

Hello, someone on the Firingline forums recommended that I post my question here. I recently bought a Plainfield M1 carbine that seemed in good shape. I was hoping to use it as a handy home defense gun. Most literature recommends using either a hollow point or soft point ammo for best effect. With the current ammo shortage, I invested in 40 rounds of Corbon DPX 100 grain JHP. It won't feed, it's not even CLOSE! The tip of the bullet just hits the lower barrel edge and stops. And this is not like it's just a little off, I mean it looks like even FMJ's wouldn't feed. Of course, I have no FMJ's to try, because they are all on backorder. I tried it with multiple magazines, no difference. I see that this rifle has a split feed ramp, right and left sides, with well over 1/8" of space between the top of the feed ramp and the barrel lip. I've never seen a firearm with a gap like that.
There was NO WAY this round was going to chamber because the front of the bullet was just stopped dead about 2mm low of the lip of the barrel. There isn't any machining on the lower barrel edge to help feeding. It's just rounded a bit all around. I've polished a few feed ramps and barrels on other guns to help feeding problems, but I think this problem is WAY beyond the few thousandth's of an inch that can be resolved by that. It seems to me that (mainly) the feed ramp doesn't go high enough and/or extend far enough forward to meet the lower lip of the barrel, or the barrel is not seated far enough into the receiver.
I'd appreciate any advice on this rifle and ammo. It's not much good to me if it won't feed decent (or any!) ammo.

Just checked two of my Plainfields. The setup on both of them seems as per your discription of your unit, although I'm confused as to your term "rounded".. Assuming that your setup is within manufacture specs, the angle of the ramp should align the round so as to shoot it over the "gap" and then get the bullet started into the chamber as the bolt moves forward.
Besides factory ammo, I've reloaded ball, SP and the Horandy 100gr SJ's with rarely a feed problem.
I'd beg, borrow or steal a couple of other rounds (G.I., commerical PMC. ,etc) and see how those feed, and then take it from there.

[Fallowt]

Thanks for the responses. Yeah, I guess the only thing to do now is to get some non-jhp ammo somehow and see if it even feeds that. I'll let you know.

[Sunray]

"...rifle has a split feed ramp..." Not out of the factory. Plainfields are exact copies of issue carbines. Mine has a solid feed ramp with a central guide ridge. If your's has a gap, the receiver is broken.

[Fallowt]

It's not actually "split", it has that center raised guide ridge you mentioned. Sorry, I didn't know how else to describe it. The ramp itself may be OK, although it looks to me like it doesn't go quite high enough to meet the barrel even if there wasn't a gap. The gap is between the top of the feed ramp and the barrel opening, which to me looks excessive since it's more than 1/8 inch. I'll try to take a picture of it and post it. Thanks for confirming that the Plainfield models are built to mil-specs, I was beginning to wonder.

[Fallowt]

I uploaded the file as an attachment. If you can see it, that gap marked in yellow is about 3.5 mm. Yes, I know it's dirty.

[jjrothWA]

that the bullets are hitting the ramp(S) 2/3 up.

Have you clean/detailed the mags? if taken apart, is the longest length of spring against the back of the mag? if not switch the spring around.

the gap is too wide, in my opinion.

[Sunray]

Your rifle is fine. Same space between the chamber and feed ramp in my rifle. I'd almost bet your problem is with the short 100 grain bullets. OAL should be 1.680". 100 grain bullets usually have an OAL of 1.600".
Don't use any factory ammo myself. My handloads only. Speer 110 grain HP's with IMR4227 feed just fine out of my Plainfield. Blows a hole the size of a grapefruit in a ground hog.
The Corbon ammo uses a Barne$ $olid copper bullet too. Pricey stuff.
Sportsman's Guide is listing all kinds of .30 Carbine ammo. Remington UMC 110 grain MC's run $22.97 per 50, $226.97 per 500 and $449.97 per 1,000. They list less expensive Wolf ammo too, but it's steel cased and not reloadable. Mind you, buying ammo on-line gets expensive fast when shipping is added. Look into reloading.
"...Plainfield models are built to mil-specs..." Yep. All milsurp parts will fit too. Never had to change any parts on mine though. Never had any issues a bath didn't fix in 30 plus years. Except for the one 30 round mag I have. It needed the mag lips opened a tic to feed properly. Did it with fine, long, needle nosed pliers.

[Fallowt]

Thanks for the additional info. I'l clean the thing up, clean and check the magazine springs, and wait for that Wolf ball ammo I ordered. Can't reload it, but it was the cheapest to just see if it feeds. I do reload, but I've never done rifle calibers. I just don't have any dies and stuff yet for this caliber, but I will. I found 500 new cases at 18 cents each that are on the way. Come to think of it, all the mags I used to check the problem were 30 or 40 rounders that may have the lip problem you mentioned, but I'll see how it does with FMJ rounds before I tinker with those. I really appreciate your advice, these forums are a great resource.
Safe shooting.

:1948:

Jon

[Sunray]

40 rounders are aftermarket. Sometimes they're just junk.
The lips needed a very wee bit of tweaking. A barely noticeable amount.

[RoninPhoenix]

from looking at your picture, it would appear to me that it needs a really good cleaning as you mentioned. Again, could be just be me, but also appears like i see some copper build up on that split feed ramp which makes me wonder if the bullet is dragging on that rough ramp. I have had similar issues in the past that were helped by polishing up that ramp, mind you, polish, not remove material. Sometimes I think a weak recoil spring might also be a culprit.