Seating a gas check . . .

[glassparman]

Ok so back to the 8mm Siamese project.

I ordered the Lee mold and I just happen to have a .329 Lee push through sizer.

Has anyone ever been successful seating a gas check in a push through sizer? Push in reverse? If so, how do I protect the nose from deforming?

Mike

 

[Brad]

I have seated many in a push thru sizer with no issues. If the taper and everything is right with the sizer the bullet will be pushed completely thru the sizing portion so the next bullet does not meet any real resistance.

 

[popper]

Only way I ever have seated GC. Nose first sizing.

 

[CWLONGSHOT]

Many do some dont...

I don't trust it, as its completely reliant upon resistance. I had a batch of lil LEE Bators ruined because the GC was not seated completely. In a perfect world it should be fine. But if the shank is fat or check tight it your using PC...

I like my NOE seater system zero guessing always absolute perfect seating as long as the person is paying attention.

CW

 

[RBHarter]

I've had more uniform success with FN pushing them base first .

With RN etc where nose first is needed I seat checks with an aircraft rivet squeezer. Kind of over kill but it ensures that they are all the way home . If there is any hard edge in the die the check will catch on it . Another bug is that the anvil has to be within.001-2 or you'll get rings and ridges on the base . This is what actually lead me to the base first solution.

 

[JWinAZ]

I also had a case where I needed to seat a GC on an 8mm with a Lee push thru sizing die. I did not want to depend on friction of the bullet to seat the GC. I made a plug from a 5/8-18 bolt and center drilled it to accept the nose of the RN bullet. That went into a Lee die turned upside down. The bullet with the finger pressed on GC then is set on the push through die punch and raised up to the plug. That seated the GC, then through the sizing die as usual. The pressure did not deform the nose and the GC was seated tight on the base. Not the speediest but no worries about a improperly seated GC.

 

[glassparman]

Yes, I see now that there is a taper in the base of the die. I'll try a couple nose first and see how it goes.

 

[KeithB]

If somebody was really interested you could probably talk me into setting you up with a shell holder adapter and one of my push through rods with a hollow end you could fill with epoxy and mold to your bullet nose. This system works real good for nose punches for in-and-out sizers. No nose deformation, no rings on your GC.

 

[Jeff H]

My experience with seating GCs on 22 cal and 30 cal have been such that I set the bullet nose down on the push-rod with a GC snapped on and then hold a steel plate over the opening of the die and raise the bullet against the plate to seat t he gas check. Then, I move the plate and push the bullet through upside down to iron the sides of the GC against the shank. If I tried to just push the bullet through, either nose first or base first, without seating the GC, I got either unseated GCs or concave GCs respectively.

EDIT: got interrupted... The examples below show both issues. Since I shoot only flat-nosed bullets, this isn't a big deal for me using the little steel plate.

I also size base first on plain-base, because if there's going to be a fin, I don't want it on the bottom. I get cleaner edges on the bases of PC'd bullets going into the die base-first also.

 

[Rick]

Sized nose first with the gas check. Sized perfectly flat and square to the bullet with a flat punch. Checks were sized first with a gas check Sizer and are an easy slip fit. If your worried about messing up the point of the bullet push it thru with the base first of a scrap bullet from the casting session.

 

[Bret4207]

FWIW- if you are using the Lee sizer system on that Lee 329 bullet in a nominal .329 barrel, consider strongly lapping out the Lee sizer to .330+. It's not hard to do with a steel rod and abrasive paper. IIRC I lapped mine out to around .332 for my 8x56R in 300 rolls on my thigh using 220 paper. The Steyr shoots cast great!

 

[popper]

Pushing base first could cause a swelling of the nose for really soft alloy.

 

[BudHyett]

Sizing nose first was recommended by David Lee many years ago. Doing this eliminated a few more fliers.

I first tried using the Star Lubri-Sizer pushing nose first which is the method David Lee used. The setup took too much time plus the original bullet lube was for pistols.

I'm now using the NOE Nose-First sizer. I like the speed and the result. I'm casting for two people and we compete in three matches per month plus practice from March through September. This takes a lot of bullets. After sizing, the bullet goes into the RCBS Lubri-Sizer in a die for lubrication. (I visually check each bullet after casting, any suspect bullet for any reason immediately goes back into the pot.)

The gascheck is hand assembled by pressing on and any that do not easily press on are checked for diameter. The increased effort while seating can indicate the mold was not closed tight enough while casting and the bullet is over diameter. These go into the practice box.

Checking the bullet as it leaves the sizer, one percent have an increased band width between the top of the gas check and the bottom of the base band. These also go into the practice box.

 

[Winelover]

I always sized and seated gas checks base first, with the RCBS LAM, in & out sizer. Works find for the relatively short pistol bullets. Not so much for rifle bullets. Could tell they were sizing out of round just by examining them. That lead me to purchase a Star sizer and size & seat nose first. At the time, I was beginning to cast for my Armalite AR-10 carbine. It would only cycle spitzer bullets, 100% of the time. The nose first Star was just the ticket, IMO. Yeah, it's slow, cause a pusher was required...........per Rick's post. But it save the integrity of the spitzer nose profile.

 

[Jeff H]

...Checks were sized first with a gas check Sizer and are an easy slip fit...

I would be interested in knowing more about the "gas check sizer."

All of my home-made gas checks have rounded edges. It does NOT seem to be a detriment to accuracy, but on my 22s, I'd really like to see a crisper edge. I can shoot .6", five-shot groups at fifty yards with a CZ 527 in 222 - a real flyweight sporter, which shoots better than it should. BUt I think I cold do better if I had a better fit on my GCs. The base of the bullet is not as round as the CGs, so I know the GC isn't fitting as well as it could. If I'm going to spend a primer, I want the most out of it I can get from my 222.

 

[Jeff H]

I recent years, I've taken to polishing the transition between the bevel and straight part of the sizing die, because there was a "hitch" which wanted to grab the leading edge of the gas checks, or just scrape bullets. I know LEE isn't applauded for quality, but they seem to have slipped a bit oin some things lately.

 

[glassparman]

Thanks for that Jeff. I see my Lee has the same issue so I'll polish it up a bit.

 

[Jeff H]

Thanks for that Jeff. I see my Lee has the same issue so I'll polish it up a bit.

Stick a 7/16" wooden dowel in a pencil sharpener and give it a whorl. This makes a nice platen for a small piece of abrasive paper. No dinking around - start with at least 320. 400, 600, 800. 400 is probably enough though. I rub white buffing compound on the bevel on the dowel and lap a nice mirror finish on it. Makes it easy.

 

[Brad]

Flair tool mod II

Got the second version of the check flair tool made. This is the absolute cats ass in flair tools. Way better than mod I. No fiddling to center a check. They come right off with no tools needed. Press ram goes full stroke. I adjusted the anvil in the press to just contact the punch with no...

www.artfulbullet.com

Check sizer, expander, whatever. In the end it makes it easier to seat a check on slightly too large check shanks.

 

[Jeff H]

Thanks, @Brad .

I started turning a spud from an arrow field-point a few years ago. I'll look for it. I don't even remember if I ever used it.