Bulged brass after seating bullet

[TDA]

Ok I figured it out. The brass is long and out of spec on some cases. Both pieces are Blazer and one is 15 thousandths longer then the other. The only solution is to ream the barrel about 5 thousandths longer to assure all pieces feed reliably. I dont want to ream my barrels but I dont see another option. You can see the difference in both just with the eye so its quite a bit.

Modifying the chamber to accept out of spec brass makes no sense at all.

Edited June 23, 2015 by TDA

[brian45acp]

Well I will say that the brass that is longer is with in spec and is .755 long. Seems my CZ has a chamber which is right on the edge of accepting brass which is near the top end of acceptable lengths.

Edited June 23, 2015 by brian45acp

[dillon]

Before reaming the chamber, check the chamber fit using only sized, empty cases. If the bullet is seated out too far it will contact the rifling, preventing the cartridge from chambering fully.

[brian45acp]

This is what I did. Took the round which didn't fit and pulled the bullet and tried using just the brass. I couldn't get the barrel to lock up with the longer piece of brass.

How could 3 of my CZs all do this? You guys are using cz and I don't hear of them all having to real the barrel. Would polishing the breech face help at all? The longer bras drags badly on the breech face as the barrel slips upward to lock into the lugs.

Those pics are with no bullet and just sized brass. So is there something I'm missing or do I need to finish ream all my CZs ?

Edited June 23, 2015 by brian45acp

[dillon]

9X19MM empty cases have a maximum SAAMI length of .754". The SAAMI chamber depth has a minimum of .754" to a maximum of .776". So it is possible for a case longer than maximum to prevent a minimum depth chamber from fully locking.

[brian45acp]

9X19MM empty cases have a maximum SAAMI length of .754". The SAAMI chamber depth has a minimum of .754" to a maximum of .776". So it is possible for a case longer than maximum to prevent a minimum depth chamber from fully locking.

Just wanted to follow up. What you mentioned was the final outcome. I have some brass that was beyond max spec some how. at .755 things start to feel sticky trying to lock the barrel as the brass slips across the breech face. At .756 is the limit and that or beyond wont chamber. I was finding .757 and .758 and those seem to make the gun quit. I decided to leave the barrels alone and since I am getting the brass so cheap its worth the extra step to check each finished round in my gun before the match. I just load the mags up and hand cycle them through to ensure they chamber. I thought of alternatives but that ends with having to buy all the tumbling equipment and media etc. I also really enjoy leaving brass where it falls and walk away. I can be more focused on whats happening at the stage and not be a brass crack head running around fighting for it along with the other crack heads.

At the match yesterday I measured brass from the CZ crowd and nobody had brass even close to .750 so of course they never heard of the issue I was having. Even the open guns spit out brass in the .740-.745 ranges. I simply got a bad few cases in my last batch and I suppose for the cost savings it is still worth dealing with. I would triple my brass expense and have to invest in tumbling and collecting it again. I feel confident entering in the match knowing all my ammo has been checked through the gun so I think that may become my new practice.

I read a great article on Brownells about head space. In short basically ammo manufactures purposefully load on shorter then SAAMI spec for brass to ensure it all feeds in even the shortest chamber. Because of that if one were trying to exactly head space the brass to the barrel and the bullet just touching the rifling for max accuracy it would be impossible on new brass. Fired brass that stretches would allow this to be more possible and the rifle guys seem to make their settings off fired brass seeing as how you cant shorten your chamber but only lengthen it. CZ must build their pistol chambers such that the minimum length is applied so that max accuracy can be attained. Since 99% of brass runs down in the .740-.750 range it means it nearly perfectly head spaces to the barrel so reaming would push that head space further away. I concluded that if I want to shoot out of spec brass or ammo I have a Glock for that

I will say these stupid LEE dies really make a nice finished round. I am all Dillon and it bugged me to try LEE again but I have to say the end result is better when speaking of the FCD. With the Dillon crimp die it was difficult but possible to get a bullet with no sign of having been loaded but it would take no more then a medium hit on the bullet puller to pull it apart. With the FCD it takes 4-5 hard hits to get it to release and there is zero signs of it having been loaded.

Edited June 28, 2015 by brian45acp

[Steve RA]

When you speak of "bulged" brass are you by any chance referring to it being "wasp waisted"? If so, that is what you want as it removes all chance of a bullet being seated deeper into the case.

I don't like, or use, a Lee FCD die as it may be OK for jacketed bullets (as they are more strongly constructed) but with lead, plated or coated they can reduce the bullet diameter. Problem there is twofold as some bullets are designed to be a few thousandths larger than bore diameter for best sealing and accuracy, also if you size the bullet and case together the case will spring back some and the bullet - being mainly composed of lead - won't. This leads to the bullet being looser in the case and more susceptible to set-back.

[brian45acp]

Yes I did read that the FCD is no good for anything but jacketed. I shoot JHP so I dont have any of those issues. I very quickly could tell that difference when I went to use the bullet puller.

Originally I did not understand that the 9mm case was tapered and the ring on the brass at the base of the bullet should be there. Some was worse then others but with the Dillon Reps advice of loosening all the lock rings and cycling the press it greatly improved and the FCD in place is a nice back up to straighten things out. Turned out none of this contributed to the not chambering issue any how but either way my reloads are more perfected so thats a plus.

For the JHP I dont see how the FCD could resize more then the diameter of the bullet. In other words all the brass below the bullet wont be resized since whats above the bullet is of greater diameter. The U die at station one will undersize the brass and the FCD at the last station would remove any of the excessive bulging at the bullet base. I believe what causes this to be more pronounced at times is the bullet seating slightly crooked and pressed one side of the brass out as it aligns it self into the brass. The ring or bulge should be even all the way around and the FCD seems to correct this if the bulge were more prominent to one side then the other.

I will go test the bullet set back and see if its more or less compared to using the standard Dillon taper die.

Edited June 28, 2015 by brian45acp

[taadski]

Just as a little follow up from my issues:

I followed Dillon's advise and aligned all my dies at the same time. I'm hoping that remedies some of my issues from the get go but I also installed the FCD. I adjusted the crimp on the lighter side and then ran a bag full of out of spec problem rounds through it (from my initial go at loading the longer 147s mentioned above). Almost every last one passed my chamber checker (plunk test) afterward. It was interesting to see the marks on the brass where it'd done its external dimension reshaping. All the rounds also ran without incident in the mentioned game gun too without any appreciable loss of accuracy. The Lee die is going to stay in place as cheap insurance.

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