problem with my 308 ammo

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typhoon4x4

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ok the gun im loading for is a colt m2012 chassis model in 308 . the gun came with a reloading data card calling for 2.797 col with 40 gr of imr4064 with a 168gr bullet. well ive reloaded for those specs. the problem im having is that it feeds but when closing the bolt i had to really force it closed but will then chamber a lot easier the second time. ive tried using federal premium 168 and feeds and closes like butter. i realize im doing something but ive measured all the rounds and every single one is within specs. im at a lose for words is the ammo good for use ??? since it will lockup??? anything i can do or pics i can post for the diagnosis?????
 
Could be a variety of issues. Fouling in the chamber, case not trimmed to length even though the col is within specs. Taking a quick look at my Lyman reloading manual it states that for a 168 gr bullet the OAL is 2.775. Please do not be offended since I do not know your level of expertise but another thing you may consider is using a case length Head space gauge.
 
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no offense takin i havent shot the colt rifle but ill check it just in case. im doing oal of different sizes to see what would work and all sizes it didnt matter .
 
typhoon4x4 said:
ok the gun im loading for is a colt m2012 chassis model in 308 . the gun came with a reloading data card calling for 2.797 col with 40 gr of imr4064 with a 168gr bullet. well ive reloaded for those specs. the problem im having is that it feeds but when closing the bolt i had to really force it closed but will then chamber a lot easier the second time. ive tried using federal premium 168 and feeds and closes like butter. i realize im doing something but ive measured all the rounds and every single one is within specs. im at a lose for words is the ammo good for use ??? since it will lockup??? anything i can do or pics i can post for the diagnosis?????
Click to expand...

1. Whether or not the appropriate COAL will be 2.797 inches will depend on where the ogive of the bullet is. It will not be in the same place on all 168 gr. bullets so your problem could be that you're jamming the bullet against the lands; in fact, I believe this is most likely the problem. To check, load some a little shorter You can load them a little shorter without changing your powder charge.

2. The question about how you are sizing refers not to the kind of press you're using but rather are you full length sizing or are you neck sizing. If neck sizing, try full length sizing.

3. It's doubtful the problem is a dirty chamber or cases that haven't been trimmed short enough.

4. I've managed to reload for 50 years without the need for a headspace or case length gauge.

5. You can do all the measuring of the cartridge you like but that probably won't elucidate the problem (except for gross deviations from specs) unless you're comparing those measurements with a chamber cast. No, I've never needed a chamber cast in all my life.

6. I have run into the problem in the past with cartridges reloaded for one gun not fitting in another (ones I had neck sized). There is a die that can save you called a body die. You can use a body die to set the shoulder of a reloaded cartridge back
 
....and, how are you checking your sized cases?

Case gage?

head space comparator?
 
I had similar problems once and being a rookie found my issue was case length. Others have already mentioned this. I now check case length every time whether the brass is new or once fired. I also learned how important it is for everything to be the same. Had I learned how to load under a hand loader that was also a match shooter that would have already been drilled into my head. In my hop a case length gauge should be included with any die set sold.
Best wishes and good luck
 
Sounds like the shoulder is not being set back enough when resizing.

Using a headspace comparator, measure a fired case vs. a sized case and see how far you are setting back the shoulder when you resize.
 
ok update it seems i was neck sizing only i did what a poster recommended and turned all the way to the plate and then went an extra 1/4 turn and my problem has gone away. so now i am full resizing not 3/4 resizing .
 
just one last question the 40 rounds ive made would they be good to shoot ? or should i just suck it up and deconstruct resize and start over???? yeah a lazy question but a huge time killer too lol
 
40 grains of IMR4064 is a tick below current minimum of 41.5 for a 168. Not enough to worry about, but that card is old. Buy a Lyman manual. Max is 45.9(Compressed). Compressed loads are nothing to worry about.
You need to check case lengths(Trim, chamfer and deburr as required only), FL resize every time(no neck sizing only, ever, for semi-auto's, lever actions or pumps. ) and watch the OAL(2.797" is ok. 2.800" is MAX. And that's from the point of the bullet to the flat of the case head, not the ogive of the bullet.) for any semi-auto. No crimp is required for a semi-auto either.
Not FL resizing will cause your issue. So will case length. Set your vernier calipres(preferably digital) to 2.015" for .308 and use 'em as a gauge to check lengths quickly.
There's no such thing as a "case length head space gauge". Cartridges do not have headspace. There are case length gauges and headspace gauges(that have nothing to do with the case), but not one in the same.
 
Sunray said:
40 grains of IMR4064 is a tick below current minimum of 41.5 for a 168. Not enough to worry about, but that card is old. Buy a Lyman manual. Max is 45.9(Compressed). Compressed loads are nothing to worry about.
You need to check case lengths(Trim, chamfer and deburr as required only), FL resize every time(no neck sizing only, ever, for semi-auto's, lever actions or pumps. ) and watch the OAL(2.797" is ok. 2.800" is MAX. And that's from the point of the bullet to the flat of the case head, not the ogive of the bullet.) for any semi-auto. No crimp is required for a semi-auto either.
Not FL resizing will cause your issue. So will case length. Set your vernier calipres(preferably digital) to 2.015" for .308 and use 'em as a gauge to check lengths quickly.
There's no such thing as a "case length head space gauge". Cartridges do not have headspace. There are case length gauges and headspace gauges(that have nothing to do with the case), but not one in the same.
Click to expand...
i agree but the rifle came with a data sheet from the manufacturer and that was the receipe they say they used to sight the rifle in. and included the target which had 4 shots covered by a dime at 100 yards
 
typhoon4x4 said:
i agree but the rifle came with a data sheet from the manufacturer and that was the receipe they say they used to sight the rifle in. and included the target which had 4 shots covered by a dime at 100 yards
Click to expand...
i was also thinking of tinkering with it but i wanted to try what they reloaded and go from there.
 
Sunray said:
40 grains of IMR4064 is a tick below current minimum of 41.5 for a 168. Not enough to worry about, but that card is old. Buy a Lyman manual. Max is 45.9(Compressed). Compressed loads are nothing to worry about.
You need to check case lengths(Trim, chamfer and deburr as required only), FL resize every time(no neck sizing only, ever, for semi-auto's, lever actions or pumps. ) and watch the OAL(2.797" is ok. 2.800" is MAX. And that's from the point of the bullet to the flat of the case head, not the ogive of the bullet.) for any semi-auto. No crimp is required for a semi-auto either.
Not FL resizing will cause your issue. So will case length. Set your vernier calipres(preferably digital) to 2.015" for .308 and use 'em as a gauge to check lengths quickly.
There's no such thing as a "case length head space gauge". Cartridges do not have headspace. There are case length gauges and headspace gauges(that have nothing to do with the case), but not one in the same.
Click to expand...
i have 6 manuels that i use the latest ones as well speer lyman and hornady.
 
I just checked my books (Some Of Them),

1) Lyman #50, shows 168gr HPBT, IMR-4064 40.0, COAL: 2.775, yields 2415fps
2) Lee Modern Loading, 2nd Edition, 41.5 yields 2518, up to 45.9 at 2766
3) Hornady #8, IMR-4064 36.1 at 2100, 41.6 Max at 2500

Hope this helps
Dan
 
Okay, for those who missed it, the OP said in post#15 that he switched from neck sizing to full length sizing as suggested by Grumulkin, and his problem went away. Not an unusual solution for a semi-auto.
 
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