Stumped, reloads won't chamber?

[TurboFC3S]

I cross posted this over on 68forums ... just looking for some help.

Alright, this is frustrating ... loaded up 200 rounds using once fired SSA brass and 115gr SMK's. Used Lee dies, which I have used before in this same gun without problem. When I got to the range I loaded up some of the lightest loads, was going to do the full workup through the chrono ... but when I chambered the first round, pulled the trigger, hammer dropped but nothing happened? Pulled the charge handle but the bolt was stuck, it wasn't closed all the way and put a screwdriver inbetween it and the ejection port and gave it a twist. Then ejected the round. It didn't look like the round was binding on anything, so loaded up another round and same thing happened. Went through probably 10 rounds, same thing ... but one did work, bolt closed fully and fired the round (2498 fps btw, haha).

So anyway, scratched my head for an hour. If I drop a round in the barrel chamber, it sure looks like it's going in all the way. And if I drop the bolt with nothing in the chamber it fully closes. All I can see is with a round in the chamber, the bolt closes except for that last little bit where the bolt rotates while the carrier moves forward. After awhile messing with it at the range I put it up and shot other guns.

When I got home I tried it in a different rifle, and again had the same problem. So all I could think of was to order some RCBS small base dies. They arrived today, and just a few minutes ago I loaded up a dummy round using them to resize, and the same thing again! My factory Hornady TAP ammo chambers fine, bolt fully closes.

So ... what the heck is going on here?

 

[Ol` Joe]

My 1st thought, is the bullet`s contacting the leade.
Is the shoulder getting a slight "bump" during the resize operation?

 

[TurboFC3S]

There is a slight ring around the shoulder after resize, right about in the middle of the shoulder.

If the bullet was hitting the leade wouldn't you be able to see where the contact was made after ejecting? I'm not seeing anything like that.

 

[hillbillydelux]

What caliber, COAL, Gun?

Sorry I didnt see the part about 68 forums.

Are you full length resizing?

 

[NCsmitty]

Either the brass is not sized right, which includes not setting the shoulder back to spec, or your bullet is seated long and it's touching the rifling.
You need to bring your sizing die down to the shellholder with a case inserted fully and check your COAL for proper dimension.
Size a case as indicated, then try fitting the case into the chamber for fit before proceeding.
You shouldn't need a small base die even for an AR.


NCsmitty

 

[TurboFC3S]

Ha, posted on 68forums so they knew the caliber ... forgot here. 6.8SPC

Loaded to 2.25", all brass trimmed to 1.675" after full-length resize.

 

[NCsmitty]

Ha, posted on 68forums so they knew the caliber

I'm guessing they didn't have an answer?

Good reason not to load up 200 rounds before checking the basics.

Are these SMK's a new bullet for you, or have you loaded these before.


NCsmitty

 

[TurboFC3S]

I guess I feel kinda silly now, gave it another 1/2 turn so the press cams over hard and loaded up a couple more dummy rounds. These chamber fine. Never had to do that in the past with the same set of dies in the same rifle.

 

[NCsmitty]

TurboFC3S, no reason to feel silly, because you'll never do that again without checking. We all learn from our mistakes.
It's a common problem that crops up once or twice a week on this forum.
Good shooting.


NCsmitty

 

[hillbillydelux]

Dont feel bad. Thats why I asked about the full length resizing. After buying my first AR I had the same issue. I was so used to loading for bolt guns I automatically backed off the sizing die to paartial size and the damn things wouldnt chamber right. Guess we all gotta live and learn

 

[something vague]

What did you give an extra 1/2 turn, the seating die or the sizing die. Just curious.

 

[TurboFC3S]

The sizing die ... but I don't understand how it would make a difference. The ones that won't chamber had the sizing die touching the shellholder lightly, the ones that do now chamber have the extra 1/2 turn so it cams over hard at the end of the pull. Once contact is made with the shellholder, how can it shove the case into the die any further and bump the shoulder back farther?

I've loaded probably 1000 6.8 rounds and thousands of .223 for AR's ... that's why I feel a bit silly. But I guess never having a problem before I just assumed they'd be alright, and didn't check first.

 

[hillbillydelux]

When adjusting for full length resizing you have to raise the ram and screw the die down till it touches then lower the ram and give it another 1/4 turn down. That comes straight from Speer #13 so I guess it does give it that extra little push.

 

[hillbillydelux]

Also if the once fired brass wasnt originally fired from your gun then thats part of the problem. If it was fired from another gun then it was "fire formed" to that chamber and not yours.

 

[Sport45]

but I don't understand how it would make a difference. The ones that won't chamber had the sizing die touching the shellholder lightly, the ones that do now chamber have the extra 1/2 turn so it cams over hard at the end of the pull. Once contact is made with the shellholder, how can it shove the case into the die any further and bump the shoulder back farther?

Was it touching the shell holder lightly while sizing a case or when the sizing die was empty. The difference might be normal stretch and flex in your press.

 

[JGAreddog]

223's are very bad about this and require a small die adjusted a little past touching the shell plate. I assume this is 6.8 in your case and the base doesn't typically bulge like 223's and "hotter" cartridges.



To all who say small base is a waste: I have tried Dillon, Lee and RCBS to date but the only one that works 100% all the time is a RCBS small base die. They also wear out after roughly 400k-600k rounds.

 

[243winxb]

Question-

how can it shove the case into the die any further and bump the shoulder back farther?

Answer-

The difference might be normal stretch and flex in your press

Another thing that can keep a round for chambering is over crimping. The shoulder will deform just enough to do what your experencing.

 

[Borg]

If you've loaded with the same dies in the same press and didn't have any problems chambering before, try putting lube inside the neck.
It keeps the expander from stretching/changing the angle of the shoulder.
If the shoulder is not the same angle as the chamber or close,, it WILL stick in the chamber.
Borg