Poorly fitting 22 hornady gas checks

[DrB]

I was seating some small caliber gas checks tonight (hornady 22 cal) and I noticed that they were flared down to about half their depth. Upon placing them onto the bullet shank they go not quite all the way to the bottom of the flare and bottom out (against the flare, not bullet base to gas check flat).

Upon seating they generally appear to be fully seated (some I am suspicious of), but there typically is some small sign towards the bottom of the bullet that one side of the bottom portion of the bullet contacted the sizing die (whereas the rest of the bullet circumference did not). If I run an unchecked bullet into the die to check seating depth, no evidence of sizing occurs. This suggests to me the gas checks initially aren't seated flat and the bullet is consequently making contact with the side of the sizing die during check seating.

Neither the eccentric die contact nor especially the possibly off square gas check base strikes me as good for the potential accuracy of these bullets. Not good at all! :)

Anyone have a suggestion for a better fitting brand of check (larger internal diameter) that should initially seat flat to bottom? Failing that any tips to get these to work would be appreciated.

Best regards,
DrB

[JeffinNZ]

What bullet are you fitting them to? Have you a gas check shank measurement?

[DrB]

It's an noe 107, and the check shank runs 2155-2160 at the base to around 217 at the top measured with a micrometer.

Using a zeroed caliper checked on a 1.0000 standard, the id of the gas check measured .2140 (+-.0005 precision).


Best regards,
DrB

[JeffinNZ]

215-216 is a bit more than I would have expected. You may have to flare the checks a little. You could try using a gas check seater however you must be careful not to inadvertently 'bump' the bullet in using such.

[DrB]

215-216 is a bit more than I would have expected. You may have to flare the checks a little. You could try using a gas check seater however you must be careful not to inadvertently 'bump' the bullet in using such.

I am already using an rcbs2 lubeamatic 2 with a gas check seater.... How would you expand the base of the check using basic tools?

I wonder if there isn't a better fitting check out there already?

[JeffinNZ]

I made a little punch from brass for expanding .30cal checks.

Another option to make you on checks.

[DrB]

I'm just experimenting with these as a sample. I'm not going to start manufacturing custom checks for a mold I don't own. :)

Yeah, need to get a lathe one of these days. Need more shop space to do that, though. :)

I'll be up at a friends with a full shop tomorrow... should be able to turn a punch then.

[cbrick]

Did you get your punch made, how did it work out?

Several years ago I gave up trying to get checks fully seated flat and square. Many of my molds simply would not accept a check fully, just as you describe they would seat slightly canted because they did not fit properly. Now one of the very most boring things I do is size all of my checks but when I install them they slip on fully and crimp on flat and square to the bullet base. My SAECO molds were the worst offenders for the checks fitting.

I have made up different types of check sizers, one is the photo below made from a Lyman "M" die with the expander (spud) cut flat and chamfered to properly size the check to fit. The anvil is made from an RCBS extended shell holder milled flat (no hole in the middle) and I use it in the Rock Chucker.

Other punches are made simply by grinding off the point of a center punch until the diameter is proper (they are tapered) for the caliber of check and chamfering the edge to put a flare on the check.

It is a PITA but I get an absolute perfect check fit, something I consider critical to long range accuracy.

Rick

[9.3X62AL]

What CB Rick said. I use punches of one kind or another, sometimes made up from center punches--or the expander plugs of other die sets. I set the checks on a pice of 2" x 4", give them a tap to flare the edges, and life is lots easier. About half of my 30 caliber GC moulds' castings require this extra step--almost all of the smaller calibers require it--and few of the larger caliber casting seem to. This may be due to my harder alloys casting a mite larger than "spec" for WW or #2 Lyman, not sure as to that.

It's ANOTHER step in the reloading process, but with all the prep and spoiling we give our brass and boolits, it's kinda like shaving hair from an elephant. The fliers nearly DISAPPEARED from my 243 and 25-20 cast loads by taking this simple step of flaring the gas check edges. Beats having to re-cast a spoiled boolit and lose/ruin a FOUR CENT gas check, too.

[DrB]

Thanks for the feedback, folks. No rick, I got to jawing and working on other projects with my dear friend who's lathe I was going to borrow, and didn't get it done.

What I did do when I got back was measure some of the unchecked bullets for min/max oal length, then gas checked them, then measured them again. I found for those several I sampled that my boolit noses were starting out .002 - .003 out of flat due to the mold halves being offset along the bullet axis (the bases were "perfectly" flat though). After seating the check, the measurements on oal stayed the same to within less than measurement precision.

Anyway, I'll see how a sample shoots, I guess, and go from there.

I am really looking forward to getting a shop built when we build a new house... I just don't have the room for a decent lathe, drill press, and grinder station right now... Yes, with patience and hand tools you can do most of what you need, but it does tend to be a PITA. :)