7mm brass won't chamber in gun (New Guy)

[Flouncer]

This was in the classifieds this AM - flowing brass . . . . regarding brass flowing and case thinning and separation discussed above. yeah, the case grew about 1/8 inch by the looks of it. Can any of you comment on this and the mechanics ? Did the belt prevent a case separation ?

It was supposed to be a Remington 700 KS chambered in 300 win mag. After shooting it once I found out that it is not a 300 win mag. I believe it to be a 300 Ackley Magnum, but I could be wrong, so Its UNKNOWN. I had no issues when firing that round, the case just came out with the shoulder pushed forward and a very short neck. I didn't know anything was wrong until I looked at the case after it was ejected. A 300 weatherby case will chamber and a 375 H&H case necked down to 30 cal will chamber as well, which makes me think its a 300 ackley mag.

 

[DWtsn]

More searching will reveal more im sure. Use this method for case bump as well as finding lands

http://forum.accurateshooter.com/threads/best-method-for-measuring-distance-to-lands.3957990/

Dusty, I researched the Stripped Bolt Method this morning and decided I would use both methods, Stripped Bolt and Hornady OAL, to see what the numbers get me. I stripped the bolt, carefully drove out the pin for the ejector while maintaining a finger over the injector to prevent it from flying across the room...AND, it still went flying across the room. I have found the spring and I assume the Roomba will find the ejector UGH. I have ordered a new ejector, spring and pin. In the meantime, I did the Hornady OAL method today and did so with two different bullets (Hornady 139gr BTSP and Combined Tech 150gr Ballistic Silvertip).

I found on the 139gr BTSP the average OAL to lands was 2.754 and the OAL to lands with the 150gr ST was 2.830. The other thing I noticed was that the 139gr BTSP had very little seating depth and that was disconcerting. The 150gr ST sat farther into the neck and I think I'd be more comfortable with that bullet for accuracy.

The last thing I discovered was that on my last order from Sinclair, Intl. the Lee Shell Holder I ordered in order to even start using my new dies, was not included in my order. So once again, more waiting!! That's going to delay me getting these same measurements with the Stripped Bolt Method.

I did have a question(S) I'm hoping the forum can answer.
Now that I've found my OAL using a "fire formed" case (brass and NOT nickel-plated brass) when I do a FL size on the brass then I size the neck, won't that change my OAL when I seat my bullet?

I'm assuming that when I FL size in order to get the shell "right" at the belt, that the shell will lengthen, then I will have to neck size to get that length back to its accurate size, minus a few thousandths. Won't all these adjustments change where the bullet now contacts the lands? Or should I have done the FL size, neck size and THEN do an OAL measurement?

 

[Richard Coody]

i believe you have confused me. let me try to understand.

first you found out why i like using the stoney point. stripping a bolt every time you try a new bullet or check for throat erosion is a bit too much work for me. one tip. when you are messing with spring loaded gun parts doing it with the parts in a plastic bag can save you some heartache.

next. you are assuming your brass is fully fireformed. how many firings? can you chamber a piece of your fired brass?

and next. when you full length resize a piece of brass you are resizing the case body and neck and if done correctly bumping the shoulder back one or two thousands all in one procedure. should have no effect on base to ogive length on a seated bullet.

as an aside. you did buy some imperial sizing wax for lubricating your cases prior to sizing didn't you? if not get some. a stuck case will put your die right out of commission.

 

[DWtsn]

i believe you have confused me. let me try to understand.

first you found out why i like using the stoney point. stripping a bolt every time you try a new bullet or check for throat erosion is a bit too much work for me. one tip. when you are messing with spring loaded gun parts doing it with the parts in a plastic bag can save you some heartache.

next. you are assuming your brass is fully fireformed. how many firings? can you chamber a piece of your fired brass?

and next. when you full length resize a piece of brass you are resizing the case body and neck and if done correctly bumping the shoulder back one or two thousands all in one procedure. should have no effect on base to ogive length on a seated bullet.

as an aside. you did buy some imperial sizing wax for lubricating your cases prior to sizing didn't you? if not get some. a stuck case will put your die right out of commission.

Richard,
Next time I will DEFINITELY use a plastic bag!! Learned a lesson there!!

I WAS assuming my brass was fully fire formed. Fired once through my rifle, allowed the brass to sit for 30 secs after each was fired. And yes, I can chamber a piece of my fired brass. Meaning??

Understood on FL sizing. I'm measuring from base to ogive so even if the brass gets "longer" with resizing that won't matter.

And yes, I do have imperial sizing wax. I read horror stories about getting cases stuck and made sure to have some. However, my shell holder wasn't sent in my last order so now I'm waiting on Sinclair, Intl to resend my Lee Shell Holder for me to start using the dies!! That was my showstopper this morning.

Lastly, I think I will use the OAL Gauge method from now on also. Stripping the bolt each time is very time consuming and problematic.

 

[Richard Coody]

yep

there is lots to learn in this hobby. takes time and experience.

it is not uncommon for it to take 3 firings to fully fireform brass. if you have measured base to shoulder datum on your factory brass and your fired brass you see it has already grown a lot. belted magnums have lots of room to grow. if you can easily chamber your fired brass it is not through growing. i explained in an earlier post at this point you want to just size the neck and not bump the shoulder. you can do that with your full length sizing die by backing off the die and slowly turning in down in small increments while sizing the case. if you watch the neck you will see the neck being sized. now you don't want to turn that die down enough to bump the shoulder at this point.

when you have fired cases that chamber tight or not at all then it is fully fireformed. then you want to screw that die down just a tiny bit more size a case and try to chamber it. when you have it set correctly you should have a difference base to shoulder datum between your fired brass and sized brass of 1 to 2 thousandth 0.001 to 0.002

most any sporting goods store will have shell holders. they are pretty much all the same with slight variations even among the same manufacturer. i mostly have rcbs and redding. i keep a set of redding shell holders in my range reloading kit.

 

[DWtsn]

yep

there is lots to learn in this hobby. takes time and experience.

it is not uncommon for it to take 3 firings to fully fireform brass. if you have measured base to shoulder datum on your factory brass and your fired brass you see it has already grown a lot. belted magnums have lots of room to grow. if you can easily chamber your fired brass it is not through growing. i explained in an earlier post at this point you want to just size the neck and not bump the shoulder. you can do that with your full length sizing die by backing off the die and slowly turning in down in small increments while sizing the case. if you watch the neck you will see the neck being sized. now you don't want to turn that die down enough to bump the shoulder at this point.

when you have fired cases that chamber tight or not at all then it is fully fireformed. then you want to screw that die down just a tiny bit more size a case and try to chamber it. when you have it set correctly you should have a difference base to shoulder datum between your fired brass and sized brass of 1 to 2 thousandth 0.001 to 0.002

most any sporting goods store will have shell holders. they are pretty much all the same with slight variations even among the same manufacturer. i mostly have rcbs and redding. i keep a set of redding shell holders in my range reloading kit.

Thank you. I've copied this and will put it in my ongoing notes. Once I get a shell holder I'll start with that process. Until then, I have a manual (one shell at a time using a mallet) Lee reloader that I can make some quickie rounds to shoot and fire-form them.

 

[Richard Coody]

Thank you. I've copied this and will put it in my ongoing notes. Once I get a shell holder I'll start with that process. Until then, I have a manual (one shell at a time using a mallet) Lee reloader that I can make some quickie rounds to shoot and fire-form them.

i can't believe you are using that old timey lee hand loader. started with one 50 years ago. suprised they still make it. hope you have a better powder measuring system then the lee dippers.

all they are supposed to do is size the neck. hope you don't mess up your brass

 

[Dusty Stevens]

You dont have to have the ejector for load development so dont slow down

 

[GSPV]

Stripped bolt method?? Remember (New Guy)!! lol

Remember me telling you above to learn to strip your bolt? This is exactly why I was telling you that.

To strip the bolt means to take the firing pin and stuff out of the bolt. So that all pressure to close the bolt on a case is due to the case and none due to compressing the firing pin.

Strip the bolt. Size a case. Chamber the case. Does the bolt handle close completely on its own? Then you adjust your FL die out a bit. Conversely, does the bolt handle stop before it is like 90% closed? Then adjust your FL die in a bit. That “almost close on its own, close with the pressure of one finger” is the sweet spot.

Now, brass varies. Especially if you purchased once fired brass (why, why, why??) And it work hardens as you resize it. You might have to accept some compromise on your FL die adjustment.

As an exercise, I suggest trying the stripped bolt test with all of your cases after resizing. See how much variation there is.

 

[old_heli_logger]

Another important "tool" for all handloaders are an assortment of reloading manuals...especially the manual that matches your bullet.
Good luck and be careful!

 

[OLEJOE]

If you partially size your fire formed brass in a FL die, it will push the shoulder forward and lengthen the case from the head of the case to the shoulder. I use the Hornady OAL gauge to set my sizing dies. Those gauges are comparators only. Your gauge with your fired brass. Measure several pieces of your fired brass from the base to the datum point on the shoulder. They should be very close to each other. Now if your brass has only been fired 1 time, you should be able to neck size it only and still fit your chamber. If it won’t, take the measurement you got and start with your FL die backed out a little ( screw it down until it touches the shell holder and back it out 1 full turn) and size a piece of fired brass. Measure that and the shoulder will probably move forward. If it doesn’t, screw it in an eighth of a turn and measure it again. Once it lengthens and starts getting shorter you only want to bump the shoulder back.001 to .002 less than the length of your fired brass. The difference between new brass and fired brass in my chamber was about .020. Once you figure out how long your chamber is (base to datum point on the shoulder) keep up with that measurement. It should not change as long as you use the same measuring tools. If you are first starting out, I know it’s a lot of stuff to keep up with. Go slow and stay safe. I’ve been reloading about 45 years and it’s still one of my favorite hobbies. I enjoy it almost as much as shooting. I hope I’ve helped without confusing.

 

[DWtsn]

If you partially size your fire formed brass in a FL die, it will push the shoulder forward and lengthen the case from the head of the case to the shoulder. I use the Hornady OAL gauge to set my sizing dies. Those gauges are comparators only. Your gauge with your fired brass. Measure several pieces of your fired brass from the base to the datum point on the shoulder. They should be very close to each other. Now if your brass has only been fired 1 time, you should be able to neck size it only and still fit your chamber. If it won’t, take the measurement you got and start with your FL die backed out a little ( screw it down until it touches the shell holder and back it out 1 full turn) and size a piece of fired brass. Measure that and the shoulder will probably move forward. If it doesn’t, screw it in an eighth of a turn and measure it again. Once it lengthens and starts getting shorter you only want to bump the shoulder back.001 to .002 less than the length of your fired brass. The difference between new brass and fired brass in my chamber was about .020. Once you figure out how long your chamber is (base to datum point on the shoulder) keep up with that measurement. It should not change as long as you use the same measuring tools. If you are first starting out, I know it’s a lot of stuff to keep up with. Go slow and stay safe. I’ve been reloading about 45 years and it’s still one of my favorite hobbies. I enjoy it almost as much as shooting. I hope I’ve helped without confusing.

Lots of great info. I've added all to my notes. Thank you.