Delete Please.
Thanks everyone. Very helpful.

What magazine are you using? Is it a 30 round P-mag, or some other type of magazine? When you put the magazine in, do you have the bolt locked back, or is your bolt forward? If the bolt is forward, when you pull the charging handle, do you let it fly forward, or are you riding it?

first off it dosn't take to people... on FTF you need to pull the charge handle and lock the bolt back with the paddle, then drop the mag and go from there.

when it jams like this have you tried yankin the change handle again or hitting the forward assist?

also when it jambs what is happening? is the bullet level and hitting the lower not the ramp?

as asked what mags? my GI issue mags sucked, went with Pmags and havn't had a FTF in 500 rounds...

Im using the standard issued 10 round mag
the bolt is locked halfway back and stuck.
No forward assist on the 15 sport
Charging handle is useless does not do anything but move freely
bullet is hitting lower, the side of the ramp if you will.
Oh and yes it took 2 people

Chief, that 10 rounder ain't standard for anywhere except Commie states!

Ok, let's try again. I'll start the steps and you finish them.

1. Load cartridges into the magazine.
2. Insert magazine into rifle.

Then what do you do? And what happens?

I am in the Commie state of Ca.
Last round fires, reload new mag, put mag back in, push button on left side to bring round up and close bolt. round gets stuck comming up from the mag and freezes the bolt from opening or closing. The mag gets stuck too. Round half chambered must be pushed down to help clear the mag

Chief,

I live in a 10 round state too. This is a 1st round issue only? So your Sport seems to be working OK, probably a mag problem. Try a few easy things first, like different ammo, seat the rounds in the mag by smacking it in your hand after reloading, seat the mag in your Sport by smacking the bottom of the mag.

Can you get a 2nd mag from a friend? You'll need another mag anyway, fortunately they are inexpensive. The last 2 I bought are Stoners from Midway for $11.99, as I recall, but I also picked up a S&W OEM mag from my local range for the same price.

Good luck.

The way the charging handle works is it can pull backwards, but not push forward. So, if the bolt is stuck 1/2 back, the charging handle should only be able to move 1/2 of it's travel. With real force (and I am NOT saying that's what you should do) one should be able to pull it the rest of the way back. But as stuck as you say it is, that might not be a good idea. See how far back the charging handle goes when it's not jammed and operating properly. If the bolt is stuck 1/2 back it should not be able to move fully to the rear without pulling the bolt carrier with it. If the charging handle comes all the way back, but bolt is still 1/2 way forward, you have an issue with the charging handle or bolt carrier.

So lets make sure we have the EXACT steps that lead to this:
1 - you've fired a last round, the bolt did lock back on last round as it is supposed to.
2 - With bolt open, old mag was removed, then you inserted another mag. This mag is well seated (double check this).
3 - You hit the bolt release, allowing the bolt full speed forward motion (never "ride" the charging handle forward).
And here, rather than having a round properly chambered, you have a very jammed rifle, where it seems the bullet tip missed the feed ramp.

Seems most likely a mag issue to me. And that's easy to check if you have friends with ARs, or friendly folks at your range.

Also, I have always found S&W customer service to be excellent, so you may want to call them and see what they suggest.

One other thing. This being a 10 round mag, I assume you are loading all 10 rounds. Some 10s I've seen (luckily I can have >10, I mainly like the 20s) are awful tight with 10 rounds in them. If you have not tried it yet, try loading just 9 or maybe even just 5 rounds and see if this still occurs.

BTW - I find dummy rounds or snap caps a great aid in diagnosing these sorts of problems, without using live ammo.

Here are some things I would try...

1. Break it down and clean and lube well. Look for unusual wear on the BCG and where parts rub together. If you see wear, oil it.

2. Insure that magazine is fully seated. Slap it in and then pull down to make sure it stays in.

3. Download by one and see if problem exists. If problem seems to go away, download by two and try. Downloading by one will make the first round feed from the opposite side of the mag, where downloading by two will put it on the same side. If it fails when downloaded by two, look at the corresponding feedramp for an issue that would keep it from feeding. At this point, call S&W.

4. Try a different magazine. If it feeds when downloaded by both one or two rounds from the step above, it would lead me to believe it is a magazine issue.

Thanks for the advice.

If this is a one time only happening, I wonder if the mag was fully seated and held in place by the mag catch or simply jammed up into the mag well at a slight angle and held in place by friction. I've seen more than one jam caused that way.

Last feeding problem I had was solved by having our last child finally leave home and get out on his own.

This sounds like a magazine related issue.

10 round mags seem to have a problem with the 1st round, I ended up disassembling my 10 rounders and attaching the spring to the follower. It made loading the last round easier but I still have a problem getting the mag seated with the Bolt forward, I have learned to pull the charging handle and lock the bolt to the rear before I put the mag in. Then I just let the bolt fly, when I have tried to ease the bolt forward it always hangs up and I was taught not to ease the bolt forward. The only time I have tried was when I was heading out to hunt and game showed up before I was ready and I didnt want to spook them. Also what brand of 10 round mag are you using. I had a problem with thermold 10's, I have had good luck with Stoner mags. I am not in a restricted state, I just like 10's for hunting and bench shooting!

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