Cases not chambering correctly?

kb007

kb007

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I'm having a little problem with some of my cases not chambering correctly. They won't allow me to fully close the bolt, or get stuck in the chamber and I have to run a rod down the barrel and tap with a mallet to get them out.

The gun is my Rem 700 LSSF TH DM in 30-06. The brass is mainly my own 1 F shot from the same gun, but I did buy some 1F brass and even got some of a guy at the range. Projectiles are a mix, but all 150 gr Hornady (SST, BTSP, SP) I like a COAL of ~3.15 for bullet seating.

As an example today I made up 80 rounds. All of the cases have been ultrasonically cleaned. I sized them using rcbs die which I thought was a full length die. All have been trimmed to proper length. Every case has been dropped into a Dillon case gauge before going further. Then today - prime, fill, seat. Once I had them done, I decided to chamber some and I had 4 of the 80 get stuck in the chamber. Maybe not a statistically large number, but still 5%. I tried to measure the cases, but there was very little diff in any measurements, maybe 1 or 2 thou in diamter at the base but that was the only diff. Only other thing was that all of the ones that would not chamber were Rem brass (likley not shot from my gun as I haven't bought any Rem ammo for that gun.) I checked back to the others that have mis-chambered and over 80% of them have been Rem brass.

Is this normal to have that many somehow mis-chamber? I've had similar #'s since I started making 30-06 a couple of months ago (proly made about 400 rounds in that ime, roughly the same fall out rate.
 
You may not be full length sizing completely. This would certainly make them hard to chamber if the shoulders aren't bumped back enough. The other possibility is also the seating depth of the bullet. You say you are using mixed projectiles. Different bullets have a different ogive in relation to the tip so you may have bullets that are getting rammed into the rifling as you close the bolt. Seat all bullets that are alike at the proper depth for the given bullet.
 
Sometime you get a rifle made with a new reamer, and a set of dies made with a reamer that's worn out. I saw this with a friends 300 Win Mag,we swapped dies and that ended the problem. If you know someone with a Set of 30-06 dies borrow them and try this. Make sure the die is contacting the shell holder when you resize.
 
likley not shot from my gun as I haven't bought any Rem ammo for that gun.
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That is not at all a coincidence, and it is not at all uncommon. If the brass was fired in a larger chamber, your dies may not be able to push back the shoulder quite far enough to chamber in your rifle, even if the dies are adjusted correctly.
 
kb007 said:
I'm having a little problem with some of my cases not chambering correctly. They won't allow me to fully close the bolt, or get stuck in the chamber and I have to run a rod down the barrel and tap with a mallet to get them out.

The gun is my Rem 700 LSSF TH DM in 30-06. The brass is mainly my own 1 F shot from the same gun, but I did buy some 1F brass and even got some of a guy at the range. Projectiles are a mix, but all 150 gr Hornady (SST, BTSP, SP) I like a COAL of ~3.15 for bullet seating.

As an example today I made up 80 rounds. All of the cases have been ultrasonically cleaned. I sized them using rcbs die which I thought was a full length die. All have been trimmed to proper length. Every case has been dropped into a Dillon case gauge before going further. Then today - prime, fill, seat. Once I had them done, I decided to chamber some and I had 4 of the 80 get stuck in the chamber. Maybe not a statistically large number, but still 5%. I tried to measure the cases, but there was very little diff in any measurements, maybe 1 or 2 thou in diamter at the base but that was the only diff. Only other thing was that all of the ones that would not chamber were Rem brass (likley not shot from my gun as I haven't bought any Rem ammo for that gun.) I checked back to the others that have mis-chambered and over 80% of them have been Rem brass.

Is this normal to have that many somehow mis-chamber? I've had similar #'s since I started making 30-06 a couple of months ago (proly made about 400 rounds in that ime, roughly the same fall out rate.
Click to expand...


A full lengh RCBS Die will have "FL" on the side and a neck sizer will have "NK" on the side. Make sure you have full lengh sizer for the one fired brass you got from your buddies.

Also. I have on occasion had the same problem. I take a black jiffy marker and coulor the front half of the case and bottom half of the bullet that sticks out the end then I chamber it again. You will see where the ink gets scraped off indicating where it is binding.
 
Something I noticed that sometimes when seating a bullet in case that it will push the neck down and blow out the shoulder a tiny bit, making the body right next to the shoulder too big. Might want to check the dimensions of your rounds that don't chamber and then compare them to cartridge specs.
 
Something I noticed that sometimes when seating a bullet in case that it will push the neck down and blow out the shoulder a tiny bit, making the body right next to the shoulder too big. Might want to check the dimensions of your rounds that don't chamber and then compare them to cartridge specs.
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That is often caused by an incorrectly adjusted seating die.
 
I would say inadequate sizing but it's only 5% of your rounds? Are the other 95% tight to chamber? Most people don't realize that FL sizing dies can increase the length on your brass if not down far enough (as is forces the case to stretch into any excess space inside die. You can get more accurate measurements by using a Hornady headspace gauge kit (and bullet comparator). The HS kit will enable you to check fired brass, which will give you a close reading of your rifle's "headspace" (generically used). Check your FL sized brass with this gauge before and during FL sizing to see where your brass is at and if it's being "sized" enough (shoulder's bumped back too).

If the brass was shot through loose military chambers (M1 etc) the brass will size but due to brass' memory effect, it can tend to grow a little or the base might not be getting sized enough. Among other variables.
 
ciphery said:
Something I noticed that sometimes when seating a bullet in case that it will push the neck down and blow out the shoulder a tiny bit, making the body right next to the shoulder too big. Might want to check the dimensions of your rounds that don't chamber and then compare them to cartridge specs.
Click to expand...

I've had this happen a few times with compressed loads. . I found if I gave a tad too much crimp, the odd case would shoulder out on me . . Pulled the bullet, resized and backed off with the crimp a tad, no problem.
 
This has already been mentioned but it deserves a definite look.......Are any loaded rounds of one particular projectile? Or is any one particular projectile not getting stuck? You say you are using one coal for a mixture of projectiles........if you are close to the lands to start with and if any of the bullets have ogives further out from the base than the others .....contact with the lands is possible. Smoke up a projectile that is getting stuck....just push it in by hand and see if the smoke rubs off the bullet.
 
Thanks for all the suggestions guys. The ones that get stuck are a mix of projectiles - all seated to +/- the correct depth for that projectile and all at least10-15 thou shorter than coal max.

Basically, I don't know how to read - dammit - I just checked the damm die set and it's an RCBS NECK die set - grrr. No wonder - d'oh! Explains why the 50 rounds of 338LM I made all fit beautifully - that die set is a FL set. Thanks g-manz35

Lesson learned - read the damm label better :(:(
 
Got a Lee Deluxe rifle die set and ran 10 of the ones that wouldn't chamber thru the FL die and voila - they all chamber properly. Then I made up 50 rounds using the FL die and all of them chambered perfectly.

Thanks all.
 
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