FGMM Fire Formed brass issues.

thumper49802

thumper49802

Sergeant
Full Member
Minuteman
Feb 6, 2008
405
1
Kingsford, MI
#1
Ok, heres the deal. I have some FGMM 308, that i fired through my M40A3. Now im reloading them, for use in the same rifle. Im using 175 SMK's. Now here is the problem. I loaded 20 rounds, i have 9 rounds that will chamber nicely, the others will bind up, not lock in, or just plain not let the bolt slide to the point it needs to. Others that come close, have distinct marring on the case and bullet. How is it, that the brass that i fire formed out of this rifle, then neck sized, and then loaded, not fit into the chamber it was fire formed in. Also, these rounds that do not work in my rifle also will not chamber in a TC Icon (it was just to see, didnt expect anything) Here are some pictures, maybe you guys can help me out.

FGMM Brass
DSC00747.jpg


Marring near bottom
DSC00748.jpg


Marring on Bullet(probably from feed ramp)
DSC00749.jpg


Little marring on shoulder area(pretty sure not a big deal)
DSC00750.jpg


This round in similar to the others that would go 98% into the chamber.

Im also very new to reloading. Thanks guys.
 
#4
Re: FGMM Fire Formed brass issues.

Sounds like your chamber is pretty tight (I'm assuming you trimmed the cases and they aren't hanging up on the step in the chambering for the case to leade).

You should set up your FL die for that chamber. Run it loose, then turn it down 1/4 turn at a time until you are just bumping the case enough that the bolt closes easily on the case. Lock the ring or mark your die so you can repeat that setting. Size your cases, then try them again with just neck sizing, you may be able to get a couple loadings before having to resize.

What chamber reamer was your barrel cut with?
 
#5
Re: FGMM Fire Formed brass issues.

i ran all the cases into a wilson gauge to check and see if i needed to trim all were 100% gtg on that. Not sure on the reamer, it is a Schneider 1:11.25 Havent had 0 issues with any factory match ammo. just a portion of the reloads, i was thinking maybe go to FL dies maybe i mushed up the brass a little on the Neck sizing (once again, not sure)
 
#6
Re: FGMM Fire Formed brass issues.

You shouldn't have had to do anything but necksize... unless, you have an
extremely tight chamber and the factory loads were hot. Federal brass is soft and
it may have stretched more than normal. Bumping the shoulder should cure them.
 
#7
Re: FGMM Fire Formed brass issues.

here is a little other tid bit of info, when i was neck sizing the first few i dont think were lubed enough, they were a little tough, then i used some more lube(dry micha), and it got a little easier, could that have done anything. With the factory rounds, it could only expand to the size of my chamber, or will it continue to expand outside the chamber on extraction? I can see that i have a LOT to learn.
 
#8
Re: FGMM Fire Formed brass issues.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: thumper49802</div><div class="ubbcode-body">here is a little other tid bit of info, when i was neck sizing the first few i dont think were lubed enough, they were a little tough, then i used some more lube(dry micha), and it got a little easier, could that have done anything. With the factory rounds, it could only expand to the size of my chamber, or will it continue to expand outside the chamber on extraction? I can see that i have a LOT to learn. </div></div>

Lubing the necks with mica won't hurt. As for your question on case expansion, the case can only expand to the dimensions of the chamber (assuming safe pressures are in order.) The case will then actually shrink back down (a very swmall amount) before you could extract the case from the chamber. And welcome to the wonderful world of handloading
smile.gif
 
#9
Re: FGMM Fire Formed brass issues.

So, i convinced myself for this rifle to buy a redding die. Also i need to know how to bump the shoulder back. I also remembered, on the second half i tried all the prepped cases in the rifle, fit like a charm, then once the load was finished it acted up, possible squish in the brass when seating bullet?
 
#10
Re: FGMM Fire Formed brass issues.

Dude, step back from the press and start from the begining.

Is your chamber clean?

If your brass fit a case guage after fire forming and neck sizing, find out from your 'smith what the specs on his reamer are.

Was the bolt tight at all on any of the FGMM?
 
#11
Re: FGMM Fire Formed brass issues.

Your chamber is very rough if its scratching the brass up that much on the shoulder as well.
Tight and rough-could be the last legs of that particular reamer-as they wear they get smaller and duller.....
 
#12
Re: FGMM Fire Formed brass issues.

chamber is dirty, not horrible though, only 50 rds. No the bolt wasnt tight on any of the FGMM while FF.What i dont get, is others from the same batch will be 100% gtg fit like a champ, lock in nice and smooth and then some wont be.

COAL is 2.800
175SMK
42 gr Varget
FGMM Brass
 
#14
Re: FGMM Fire Formed brass issues.

well i also noticed a little ridge on case about 1/8 inch from the bottom. It covers about 1/4 way around. Its not huge but noticeable if your really looking hard. At this point im chasing so many monsters im already sick of this.
 
#15
Re: FGMM Fire Formed brass issues.

I would suspect the chamber. You might try some WRA brass as it is far harder. A once fired case should rechamber in the rifle it was fired in. If it will not you have a chamber problem. Even my "springy" 1895 Winchester lever rifle will rechamber a once fired Hornady light magnum. Time for a trip back to the smith. Good shooting!
 
#16
Re: FGMM Fire Formed brass issues.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Captain Kick-Ass</div><div class="ubbcode-body">did you bump the shoulder back .002? </div></div>

i have had the exact same thing happen and i bet you it is the shoulder...
 
#17
Re: FGMM Fire Formed brass issues.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Mr. Humble</div><div class="ubbcode-body">I would suspect the chamber. You might try some WRA brass as it is far harder. A once fired case should rechamber in the rifle it was fired in. If it will not you have a chamber problem. Even my "springy" 1895 Winchester lever rifle will rechamber a once fired Hornady light magnum. Time for a trip back to the smith. Good shooting! </div></div>

but why are almost half good? then the other half problematic when its all the same brass. The prepped cases chamber good. its after the bullet it seated. It cant be the chamber.
 
#18
Re: FGMM Fire Formed brass issues.

Measure the neck width (with bullet seated) on ones that will chamber and ones that won't. If your chamber is tight necked a little more brass flow in ine case to the next may make a difference.

Who built your rifle and what chamber reamer did they use?

What kind of neck sizing die did you use?

 
#20
Re: FGMM Fire Formed brass issues.

You probably have the collet die turned down just a little too much. I always start my die loose and tighten it down until there is just enough tension to "cam over" the press, then turn down incrementally untill my inside nect diameter reads .304. You will have to readjust for different brands of brass as the neck thickness determines the final adjustment.
Hope this helps, as always YMMV
Rob
 
#21
Re: FGMM Fire Formed brass issues.

Ill go through and check all the suggestions you guys gave me. This is just so frustrating right off the get go. I Still dont understand how half is good and the other half is tweaked, by using the same method. I dont understand how my chamber can be messed up. Its got to be something im doing during the process.
 
#24
Re: FGMM Fire Formed brass issues.

Use a systematic method to find your problem or problems.
Look at your process one thing at a time.

I suggest get 20 more once fired cases.
Run them all through the rifle just to double check that yes they all do fit.
Run one through the sizing die, then try it in the rifle, repeat this with all 20. If they all go this is probobly not your issue.
If you want to neck size only then start that way. If you want to bump the shoulder back then work the die down as suggested before a 1/4 turn or so at a time.

I prefer to trim after sizing. I trim every time, whether they need it or not. My point here is make sure they are all trimmed to length, and chamfered/deburred.

Now seat a bullet in a case and try it in your chamber. Did it fit? Repeat this with all 20. You may want to do this step with out powder, your call.

A couple of possible issues...
Sizing...
...Expander ball dragging on the way out stretching neck/shoulder.
...neck sized to small, causing problem when seating bullet

Seating...
...Die set too low causing brass to be "squashed" when seating bullet.
...Bullet set too close to lands, jamming in to the rifling.

You may have an out of spec chamber, But if factory ammo fits fine, I wouldn't start blaming it until you have double checked your reloading process.

Halfnutz


 
#27
Re: FGMM Fire Formed brass issues.

well, for some reason after tracing it back, and checking at each step. After neck sizing and checking OAL on case length they come up just under 2.015 and under. Well it worked on the majority of them but we have bad cases 3 out of 10. So I went with a FL die, and just full lengthed them trimmed them up and wala. It seems that during the seating process is where they mess up. I check and rechecked the setting up of the die, turned in until it hit the mouth and then did the 1/8 to 1/4 turn like it says, and seated the bullets in incriments at a time until i hit 2.800 COAL. and its hit or miss. like i said 3 out of 10 were bad only. So right now im just feeling like going with FL sizing all the time. Ill keep messing around with neck sizing until i get it. Plus im getting a redding 3 die set. Just to clear it up the FL sizing group was PERFECT! like i figured it would since its back to sammi i believe?
 
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