Neck bulging with ttsx

Raudy707

Well-Known Member
Joined
Apr 16, 2018
Messages
716
Location
Mendo
Has anyone had trouble in the past with the gas checks leaving bulges in the case necks? These brass are 5 shots deep out of a 270 win and I'm using 130 grain ttsx bullets.
IMG950575.jpg
 
use a VLD type chamfer tool , as mentioned above . if you look closely at the picture you will see copper at the neck / bullet . I see it on the middle , and the right , you are scrapping copper off the bullet during seating . I'd say putting a good chamfer on the case mouth , and dip the bullet base in powder graphite will solve your problem .
 
morning, jimbires is right about the chamber tool.
put some lub in the bullets. I had some loads due the same thing
with different bullets. I shot them. with next load I I I half neck sized
the casings. justme gbot tum
 
What do you mean 'gas checks'?
If your brass is being sized down excessively, a bulge will be visible when a bullet is seated no matter the type.
Can you please tell me you haven't fitted gas checks to the rear of your bullets.

Cheers.
Pretty sure he is referring to the "driving bands" on the barnes grooved style bullet but using the wrong terminology-- it's almost impossible to crimp a gas check to the bottom of a solid copper boat tail bullet

To the op, so he can put it into his vocabulary "hat" -- without getting too in depth- a gas check is a copper "cup" that is crimpeed/swedged" to the square bottom edge of an all lead bullet -- its intent is to reduce or eliminate extreme lead fouling from higher velocity lead bullets (example would be 357 magnum, 44 mag, 45-70 etc) , most often used, but not reserved exclusively for straight-wall pistol & rifle cartridges
 
Last edited:
In addition to a good chamfer on the inside of the necks (I also see copper cuttings on loads 3 &5 at the case mouth), you could also try a .275" expanding mandrel to accurately size those necks to .002" neck tension. I bet they are quite tight by the looks of those loads.
 
I'm thinking that you are using an incorrect nomenclature, I don't believe that you can put a gas check on a jacketed bullet; and....the Barnes TTSX bullets are jacketed bullets. First question does the bulging happen with any other bullets or just the Barnes bullets. From the photos it looks like what Laelkhunter wrote in his reply could be happening. You could have you seating die set a little too low where it is crimping the mouth of your cases. I don't use the TTSX bullets in my .270, however I do shoot a lot of Barnes bullets in my 35 Whelen and 358 Winchester. If the case mouth is not chamfered properly you will get scraping of the bullets, like in the far right cartridge in the photo. I also use a nylon brush with graphite on it to lube the case mouths before sizing. I've found the jackets on the Barnes bullets to be softer than regular jacketed bullets. I also use a piece of "4 O" steel wool after I chamfer that case necks to smooth up the sharp edges made by the chamfering too. lOr you could have an undersized expander ball in your resizing die.. Recently I purchased a Sinclair expander mandrel tool for my .270AI, it made a great difference in resizing the case necks; after the .270 expanding mandrel I bought one for my .35 calibers. The first time that I used it, I could not believe the difference between it and the expander ball that comes with the regular die set. All of the responses you've received here are all good suggestions. Did you try measuring your brass to see if the brass fell within the proper dimensions before seating the bullets. Try checking the depth of your seating die to make sure that it is not just kissing the top of your cases while seating your bullets; your .270 brass could have stretched a bit. Run the ram up to the top, then run your seating die down until it just hits the top of the casing, then back it off a half-turn and see what happens to your reloads.
 
I apologize I was making this post in haste and didnt use the correct terminology. What I meant was the pressure reducing bands that are used to relieve gas pressure not gas checks. I have a VLD chamfer tool on order. And a new expander ball. Thanks for all the replies and help so far!
 
Generally, these are called cannelures.
I would say that we have both factors here, a bit of copper is under there and I think the crimp is too hard and is more the cause of the bulges. Look at the middle crimp and the depth of the crimp just to L of middle.
 
It looks to me like your seating stem is adjusted too short causing the die to contact the case necks and wrinkle them. If you are trying to put a roll crimp on the case, you need to seat the bullets a little deeper so the crimp will be over a groove. I wouldn't want a crimp on them.
 
Last edited:
Warning! This thread is more than 5 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.
Top