Has Anyone Made A Gas Check (Cap) Punch ?

[longbow]

I will take a look in my recovered boolit bin to see what I have. Not sure if I still have any but I did recover some Lyman 31141's shot from my .308 both with and without gas check and I had some SEVERE gas cutting without gas checks. These boolits were shot into heavy wet snow so were virtually undamaged by impact.

Yeah, the lead does not actually melt, it is stripped away by the high pressure gas blowing by. Also, as what Chicken Thief says, if you use a gas check that doesn't seal the bore then you will very likely get similar gas cutting to what you get with no gas check.

Now, having said that, a lot depends on powder choice, pressure curve and max. pressure. I shoot lots of .44 mag plain base form my rifle using full house "J" bullet loads and have almost no leading. However, I find that my .30 cal. guns are not as easy to load for with PB boolits and seem to need a gas check even at lower pressures to perform well. Part of that may be the faster twist and the pressure curves. That much is beyond me.

Anyway, if I can find a good example of a gas cut boolit I will post photos.

Longbow

[DoctorBill]

longbow - Absolutely GREAT if you can SHOW what is said about the so called "gas cutting"
effect on a bullet ! Something what scientists would call DATA, not "sounds good to me" stuff.

As to the powder - yes, that "sounds good to me" !

I - being an old phart - like to use reduced loads to save my old man shoulder.
A good load for me is either Black Powder (or a substitute) or TRAIL BOSS which
is a bulkier powder giving a nice round w/o beating one's shoulder to pieces !

So - I am not very worried about 'gas cutting' with my loads.

Even so - I wanted a Lathe/Milling project and the Aluminum Gas Cap devices
seemed a likely candidate.

Chick Thief - YOU can pass an Oxy-Acetylene torsch over the back of your hand,
if you want ! Ha ! lol No way I would do THAT !
I do do it in my Chemistry Class to show the difference between a normal flame
and STEAM - which will burn the stink out of you IMMEDIATELY !

As above, my loads are low power.
Were I to shoot hot loads, then I'd go for Copper Jacketed bullets !

So...I am eagerly awaiting some EVIDENCE of actual 'gas cutting' to be
posted here !

BTW - PP Cast Bullets use a CARD DISK between the Bullet and the Powder
and from what I read (Paul Mathews) is quite sufficient to protect the bullet
base from damage.

Onward ! "Different Strokes for Different Folk. Whatever floats your Boat."

DoctorBill

[longbow]

DoctorBill:

Nope, haven't looked for an examples of gas cutting yet but will shortly. I know 303guy posted some a while back and they looked a lot like what I had (and hope I still have). The severe examples almost had the entire driving bands "smoothed" off.

On another note, controversial as it is, I use COW filler under PB boolits from my home made moulds. Without filler they tend to suffer gas cutting at anything beyond mild loads but will filler they can be pushed harder though I have not really ventured into extreme cast boolit velocity... yet.

I am lazy and don't like applying gas checks and also cheap so don't like paying for them. I made my own gas check maker to solve the cheap part but it doesn't solve lazy. Filler helps there as it is pretty easy to add COW to mid neck then seat a boolit. One does have to work up loads from scratch though! You can't just go adding filler into any old load.

I recently got my best groups ever from my No. 5 Lee Enfield using smooth sided then knurled boolits from my home made mould with COW under the boolit. Groups were running a bit over an inch at 50 yards which so far is better than I have managed with commercial moulds and gas checked boolits.

if you are running mild loads you probably do not need a gas check though as you say, making stuff is fun.

Longbow

[Chicken Thief]

Found a 25 cal and a 32 cal in the heap.
No burning/Melting at all.

[longbow]

Well, I dug through my recovered boolit bin and I do not have any of the really bad .30 cal boolits but I did find a number of .44 boolits with gas cutting. Some of these are smooth boolits from a home made pushout mould and some and a couple are Lyman 429421's. It is pretty obvious which are which.

Here are the photos:



You can see smooth "gouges" along the lands (mostly) on the boolits (rifling groove) on several and what I call "nibbling" along the edges of the bases on others.

These are "left" and "right" photos with the top right boolit in both being a Lyman 429421.

From top left to right on "left" photo:

- fairly smooth boolit and not easy to see but there is a "gouge" from gas cutting where the flash shine is
- quite clear rifling with "nibbling" along the bottom edge
- bad gouge in the middle where gas cutting removed quite a swath of lead
- another with "nibbling" along the bottom edge
- Lyman 429421 with clear rifling

From bottom left to right on "left" photo:

- first three boolits all from home made mould show considerable "nibbling" along the bottom edge
- Lyman 429421 shows nibbling along the bottom edge
- next boolit shows a deep cut along the rifling just to the right of center
- far right bottom shows "nibbling" and a long gouge along the rifling centered in the photo

From left to right in "right" photo ~ bottom row:

- same boolit as above right below Lyman 429421 at top right ~ you can see another long gouge just right of center
- triangular gouging left, center and right on boolit lands
- fairly severe gas cutting all around the bottom
- next one doesn't show up real well but more gouging (if you zoom in you can see it if resolution on shrunk photos is good enough)

The Lyman 429421 casts about 0.002" under groove diameter and was almost always a problem with leading and gas cutting.

The boolits from the home made mould are about 0.002" over groove diameter and generally do not give me a problem with gas cutting unless I push them to max loads and with faster powders. IMR4227 is usually okay but Blue Dot was responsible for much of this gas cutting. I loaded up some max. loads with Blue Dot and did some penetration testing into wood. Most of these boolits are from that group.

For the most part not as severe as the .30 cal. boolits I can't find but some of these are pretty bad.

So that's what I've got for show 'n tell.

Longbow

[DoctorBill]

I saw some Aluminum Flashing rolls at Home Depot (1' x 7') for $8.

I don't know the thickness and NO ONE there had any calipers, so tomorrow
I will go back with my trusty Digital Calipers to see how thick it is.

Felt like maybe 20 to 15 thousands, but I'm not that good yet with my
"finger calipers". I know what 4 thousandths from Pop Cans feels like.

A metal place here in Spokane (ALCOBRA) wants $20 for a 1' x 6' x 0.020"
piece of soft Aluminum sheet. I figure that I might get 1200 Gas Caps out
of that if I cut 0.625" Dia Disks to make them out of. MOL

Wow ! - This may only be half the price of buying them made out of copper !

45 cal Hornady Gas Checks are $41 per 1,000 at Buffalo Arms in Idaho and they are back ordered.
Thank you so much Obama !

DoctorBill

[Chicken Thief]

I saw some Aluminum Flashing rolls at Home Depot (1' x 7') for $8.

I don't know the thickness and NO ONE there had any calipers, so tomorrow
I will go back with my trusty Digital Calipers to see how thick it is.

Felt like maybe 20 to 15 thousands, but I'm not that good yet with my
"finger calipers". I know what 4 thousandths from Pop Cans feels like.

A metal place here in Spokane (ALCOBRA) wants $20 for a 1' x 6' x 0.020"
piece of soft Aluminum sheet. I figure that I might get 1200 Gas Caps out
of that if I cut 0.625" Dia Disks to make them out of. MOL

Wow ! - This may only be half the price of buying them made out of copper !

45 cal Hornady Gas Checks are $41 per 1,000 at Buffalo Arms in Idaho and they are back ordered.
Thank you so much Obama !

DoctorBill

But you gets to do all the work yourself for that reduced price + doing the dies and burning gas for the alu

[Cane_man]

dup post- del

[oldred]

I have been following this thread and find it very (extremely!) interesting but I have a question. My plan is to build a check maker for the Lee 459-500-3R which is a plain base bullet of non-check design. Could someone tell me what would the ideal dimensions be for the finished check? Metal thickness? ID before crimping?

[Cane_man]

Where did everybody go ?

I appear to be all alone.....

DoctorBill

DB, to add a little food for thought, I just made a plain base gas check maker to use with aluminum beer cans that will both punch and form with one stroke:



this was not my idea, but what makes it different is that the nose of the punch forms the check and then cuts it, all i do is chuck the tool up in the lathe and hit the end of the die body with a rubber mallet and the checks come shooting out:



i made the die body from some bronze i had laying around and the punch was turned from a $10 1/2" bit from home depot... i put a spring behind the die body and it pushes it back into place... a very simple and cost effective design



as you can see these aren't picture perfect square cups, but more like little bowl shapes due to how the nose is shaped, but the boolit fits right in and the sides swage up when using the Lyman 45


btw - Edsmith mills out the cone shape of the punch base by using a tile bit!


"whatever blows your hair back"

[Cane_man]

I have been following this thread and find it very (extremely!) interesting but I have a question. My plan is to build a check maker for the Lee 459-500-3R which is a plain base bullet of non-check design. Could someone tell me what would the ideal dimensions be for the finished check? Metal thickness? ID before crimping?

this is what i did:

for the plain base check the disc OD = boolit OD + (2 x material thickness) + [3/4 x (2 x boolit base band height)]

hope that makes sense!

[longbow]

oldred:

You will want to use thin soda/beer can material of about 0.004" thick for checking PB boolits.

The finished check should have a slight flare (very slight) and be just large enough to slide onto the boolit then swage in in a sizer. The disk size for .45 cal. PD should be 0.537" according to my reference. That is the punched disk before forming.

Longbow

[Bulldogger]

Wow ! - This may only be half the price of buying them made out of copper !

45 cal Hornady Gas Checks are $41 per 1,000 at Buffalo Arms in Idaho and they are back ordered.
Thank you so much Obama !

DoctorBill

Good Ole' Barry is the U.S.'s #1 firearm and ammunition salesman of the year since late 2007 and counting. It's funny though, I can't recall ever seeing a figure in his "jobs" reports that credits ammunition and firearms manufacturing increases. For some strange reason his minions who gin up these reports focus on other areas.
I just wish he'd relax a bit, so's those of us that aren't jillionaires can afford some reloading and wildcatting components.
BDGR

[Bulldogger]

And now with a slightly more relevant reply.
1) I can't add anything to the discussion of proper thickness or gas cutting or all that, but I sure do love to read about it because...
2) I dream of having a lathe and mill and all that (and sadly, know where they are and see them every time I visit a retired machinist friend who would practically give them to me but I live in the city and spend all my $$ on child support and wah wah wah) so THANK YOU for posting these interesting pictures and descriptions!!!
and
3) What the H-E-double Hockey Sticks are you making Thermite for? I've always wanted to make Thermite, and PLEASE, PLEASE, post some pictures and/or videos of the finished product in action....

Bulldogger

[DoctorBill]

Been working....standing at the Lathe just kills my back ! Lord !

I cut a piece of hot rolled steel rod (has hard scale on it) down from 3/4"
to 0.628" for the Punch Ram. I Muriatic acid wash off the scale first.



After getting REAL close, I filed and sanded to where it just went in a ways,
then lapped with Flitz Metal Polish to where it fits REAL nice in the Punch Body.



I presume some of you 'old hands' at metal working are cringing at my amateur
work, but this is how I am going at it. Hot Rolled Steel is CHEAP and easy to cut.

The body comes from a piece of metal that Buckshot sent to me when I got my Lathe.

I will now Thread the Punch Body to 12 TPI (1.25 inch for the RCBS Press),
cut a Shell Holder end button in the Punch Ram, then Cut TWO slots in the
Punch Body to slide the Aluminum Strips thru (using my Harbor Freight Band Saw).

As I said previously, I intend to mount this Punch Body upside down from normal
to cut with the ram against the strong portion of the Punch Body instead of the
norm of punching against the weaker portion on top of the slot.
Does that explanation make sense ? See post # 11
http://castboolits.gunloads.com/show...=1#post2157701

I hope some of you are getting some good or at least some entertainment out of
these posts. Get a Lathe - even a cheap one - it is a blast !

My back is killing me - need a back brace to stand at the Lathe for any length of time !

DoctorBill

PS - Bulldogger - I'm a Chemist and at heart a small boy who likes to phart
around making explosions, fire, and sparks ! Instead of tossing my swarf, I thought
"why not make something from it ?" If it works, I will post pictures here.
I have a LOT of Steel swarf but not much Aluminum swarf.....

[Cane_man]

^^^ how do you turn threads on your lathe? i have a small bench top lathe but never learned how to do it...

[DoctorBill]

Cane Man - Holy Thread cutting Batman ! Are you serious ?!

There are many Links on the internet and on You Tube about that subject.

As for me - I turn the Chuck by hand to thread because I am Chicken S__t to
use the lead Screw Feed.... So I made a "Hand Crank" that I slip into the
other end and turn the work by hand. It feeds too fast for me !



Bought a used Hand Crank at a local Machine Store - Made into this.



I split the pipe end and it is held in place by a sliding nut that expands inside
the Main Shaft.





All this is 'somewhere' in this forum - can't remember the link though !

If you want to do this (?) Google up the following, ....threading+hand+crank+lathe

I DO NOT disengage the cutting tool, but back up BY HAND and then continue
cutting by advancing the Top Slide.

If you lose the correct feed setting by disengaging the feed lever, then bad things
can happen.....There is a "Threading Dial" which I have yet to master. Scary.

The Top Slide is set to 29°. You need a 60° cutting tool and a 60° Center Gauge
to make sure the tool is set correctly.

Set ting it up is correctly is of paramount importance or you'll screw it up (no pun
intended).

Other than that, I'd say, just start by doing threading on an Aluminum Rod of the
correct diameter and PRACTICE.
You Lathe should have the Driving Gear selection of Normal and Metric threads in
the manual. Different for each Lathe.

Good luck. It is not as bad as it looks when you are starting out, but practice on
some soft metal several times before trying anything that you have spent a lot
of time on making.
Several people who frequent this forum will probably chime in - like Buckshot.

I have a "Master Machinist" friend who's brain I pick whenever I have serious questions.
If you know a machinist - pick his brain ! Most are only too happy to help you !

It's like they want you to learn Lathing and Milling - so that YOU TOO can spend
gozillions of bucks on Tooling like they have had to do !

DoctorBill

[Cane_man]

thank you DB, yes, youtube is your friend i should have looked there first...

[DoctorBill]

Right now, the biggest hassle for me is setting up the proper gears to get the TPI
I want. It is a PITA.

YOU may want to use the feed and indicator dial, but it feeds fairly fast and then
resetting the depth and using that indicator dial is too much for my feeble mind
to handle. My friend showed me but said, "Be careful !"
If you get it wrong, your work is destroyed.

I'd rather use the hand crank thingie and I spend A LOT OF TIME on the "setup".

DoctorBill

[Chicken Thief]

I have made a "complete" thread-gear list for my lathe with this:

Changewheels made by a Canuck bloke.
Can be downloaded here:
http://www.downloadplex.com/Windows/...js_238822.html