rounds not going under extractor/ nas3 cases

[Darthrader18]

I've searched and talked to a few people and can't figure out a reason for this issue. so occasionally with multiple 140s and 170s the round will chamber but the extractor will not be over the rim of the case, so the gun is out of battery. all of my mags are around .345 rear -.355 front. extractor is set at 1.125lbs of resistance, when I originally had the issue the resistance was at 1lb. the weirdest part of this it only happens with the shell shock nas3 cases. If i use brass cased ammo no issues. my rounds do tend to sit forward in the mag after cycling through. 9 major rn at 1.161 oal. been running this oal for 2 years. now just starting to have this issue when I tried to switch to the nas3 cases. I watched a video from atlas saying if the rounds are being pushed forward in the mag, then to radius and polish the bottom of the breach face. I did this and see no change. I am at a loss as what to try next. all 170s have new springs, 140s still have old springs but im having issues with all the mags. 

[hump]

Have you tried the rounds in other open guns?

[Darthrader18]

3 minutes ago, hump said:

Have you tried the rounds in other open guns?

I have not but I know a few open shooters that use these cases and have no issues. 

[MadBomber]

What are nas3 cases?  If your gun runs with everything else, stop using nas3 cases.  Cull them out.  Problem solved.  If that still doesn't work, rechamber to 38 SC, problem fixed.

[superdude]

1 hour ago, MadBomber said:

What are nas3 cases?  If your gun runs with everything else, stop using nas3 cases.  Cull them out.  Problem solved.  If that still doesn't work, rechamber to 38 SC, problem fixed.

 

https://www.ssusa.org/articles/2018/6/27/handloading-shell-shock-technologies-nas3-cases/

[sauza45]

Extractor tension seems light to me. 1.125 is 18 oz I set mine at 28 to 30 oz. weigend recommends setting to 25 to 28 oz

[Darthrader18]

2 minutes ago, sauza45 said:

Extractor tension seems light to me. 1.125 is 18 oz I set mine at 28 to 30 oz. weigend recommends setting to 25 to 28 oz

I've tried heavier this has been what has worked best with my normal brass cases just trying to figure out how to get these nas3 to work. I've always seen people say around 18-22oz but hey no two open guns are anywhere close to the same lol 

[Specialneeds]

What is the issue with heavier extractor tension?

 

Sounds like maybe there are other things at hand. Perhaps the centerline of extractor channel to firing pin channel are not in spec? If this measurement is off.. you are right, different tensions are needed. Alongside potentially other accomodations. If the tension needs to be that low, your extractor centerline may be a bit closer to the firing pin centerline than specification calls for. Is the extractor catching the rim at an odd angle? Perhaps polishing it with some fine stones will help.

 

I am not sure how I feel about those steel and aluminum cases..

 

Man, I would personally spend the bucks and run 38super/9x23 with starline brass. All that noise.. seems like a lot could go wrong with a bimetal case.

 

Could not a person electroless nickel coat their brass if they wanted that 'extra lubricity'? Either way, I thought the trend on nickeled casings was implied for carry ammunition to resist rusting and draging in magazine.

 

Nickeled tubes and well polished brass ought set you straight there. Even a well polished steel tube with some turtlewax buffed inside/outside.

 

You will need to investigate more to be certain of the issue.

 

In closing, I thought steel casings did not seal the chamber as well. Resulting in a more dirty firearm and less muzzle velocity.

 

Best luck, keep us posted.

 

SpecialNeeds

[Darthrader18]

9 minutes ago, Specialneeds said:

What is the issue with heavier extractor tension?

 

Sounds like maybe there are other things at hand. Perhaps the centerline of extractor channel to firing pin channel are not in spec? If this measurement is off.. you are right, different tensions are needed. Alongside potentially other accomodations. If the tension needs to be that low, your extractor centerline may be a bit closer to the firing pin centerline than specification calls for. Is the extractor catching the rim at an odd angle? Perhaps polishing it with some fine stones will help.

 

I am not sure how I feel about those steel and aluminum cases..

 

Man, I would personally spend the bucks and run 38super/9x23 with starline brass. All that noise.. seems like a lot could go wrong with a bimetal case.

 

Could not a person electroless nickel coat their brass if they wanted that 'extra lubricity'? Either way, I thought the trend on nickeled casings was implied for carry ammunition to resist rusting and draging in magazine.

 

Nickeled tubes and well polished brass ought set you straight there. Even a well polished steel tube with some turtlewax buffed inside/outside.

 

You will need to investigate more to be certain of the issue.

 

In closing, I thought steel casings did not seal the chamber as well. Resulting in a more dirty firearm and less muzzle velocity.

 

Best luck, keep us posted.

 

SpecialNeeds

I can't remember exactly what the issue was when I had too much extractor tension but I know when I got it to 18oz it ran like a champ. All my struck primers all appear to be dead center.  No issues at all running brass. It seems the nas3 are more slippery than brass so they are being pushed further in the mag. And too far forward to catch under the extractor.  Extractor and bottom edge of the breach face are recently polished and free of burs or dings. 

[jstagn]

Chased this very “push feed” problem on a limited gun . The space between the extractor and the breech face needed to be increased, even if is in spec. I got a tuned extractor from Brazos, problem solved.

[Furrly]

Get rid of the brass!!! It does not look conducive to reliable feeding 

[Specialneeds]

The comment about changing extractor tolerance is a solution.

 

What happens if increasing coal? Is the barrel throated enough to accomodate a longer length? This may be an alternative solution.

 

Are you sure those cases are 'proper spec'? The rim and all.

 

Lastly, your extractor has little to do with the breechface concentricity to firing pin centerline. If the barrel is square to the breechface and the firing pin is centered, the extractor will 'flex' as designed.

 

[Darthrader18]

1 minute ago, Specialneeds said:

The comment about changing extractor tolerance is a solution.

 

What happens if increasing coal? Is the barrel throated enough to accomodate a longer length? This may be an alternative solution.

 

Are you sure those cases are 'proper spec'? The rim and all.

 

Lastly, your extractor has little to do with the breechface concentricity to firing pin centerline. If the barrel is square to the breechface and the firing pin is centered, the extractor will 'flex' as designed.

 

Cases are in spec and very consistent across multiple cases. Unlike brass which has variance from manufacturer to manufacturer. Nas3 seem to be in the middle of the numbers if measured for the same part on brass variance. 

 

Barrel can accept a longer oal. I've gone up to 1.181 with brass before. Have not tried with the nas3 cases. 

[Specialneeds]

Try playing with coal first?

 

Extra space between the extractor face and breechface can be a bad thing.

 

Best luck.

 

I am still not convinced about this nastree nasty steel case.

[theWacoKid]

1 hour ago, Specialneeds said:

Man, I would personally spend the bucks and run 38super/9x23 with starline brass. All that noise.. seems like a lot could go wrong with a bimetal case.

 

"Seems like" is not objective.  Engineering analysis is.

 

19 hours ago, Darthrader18 said:

I've searched and talked to a few people and can't figure out a reason for this issue. so occasionally with multiple 140s and 170s the round will chamber but the extractor will not be over the rim of the case, so the gun is out of battery. 

Brandon, I think for this to happen there has to be non-controlled feeding.  What I mean is the round is being released from the mag before it has come under control by the extractor.  Probably can be fixed by some combination of playing with the mag lips, adjusting the height of the mag in the gun, and/or increasing the distance between the extractor hook and the breech face.  Not sure why these cases seem to be the culprit, but there's always a reason.

Edited December 6, 2019 by theWacoKid

[Ming the Merciless]

23 hours ago, theWacoKid said:

 

"Seems like" is not objective.  Engineering analysis is.

 

Not sure why these cases seem to be the culprit, but there's always a reason.

 

Magnetism?  Are you picking up the nas3 cases with a magnet? 

[theWacoKid]

40 minutes ago, Ming the Merciless said:

 

Magnetism?  Are you picking up the nas3 cases with a magnet? 

 

I'm not, but they are magnetic. Don't see how that will play into this mystery. 

Edited December 7, 2019 by theWacoKid

[Darthrader18]

2 hours ago, Ming the Merciless said:

 

Magnetism?  Are you picking up the nas3 cases with a magnet? 

The cases I've been shooting are all brand new cases never loaded never been near a magnet in my possession. 

[Darthrader18]

After speaking with one of the popular builders I have found that there is rotational play in my extractor. I have an egw hd and I use to have a aftec, I did not replace the fps when I put the new extractor In, this was 2 years ago.i have ordered a new fps it should be here next week I'll try that and see what happens. Shot the gun today using brass, no malfunctions and won HOA.