Adding Gas Checks ?

Marco Califo

New member
I do not do much rifle lead bullet reloading, but I have a box of Magnus 308 cast bullets for range use on steel plates.
My question is: To add the gas checks, what minimum equipment do I need/require?
>I do not currently size or lube bullets, and do not have the equipment.
 

Recycled bullet

New member
I do not do much rifle lead bullet reloading, but I have a box of Magnus 308 cast bullets for range use on steel plates.

My question is: To add the gas checks, what minimum equipment do I need/require?

>I do not currently size or lube bullets, and do not have the equipment.
You need 1) bullets with an appropriate gas check shank 2) correct size gas check I have only used Hornady others have recommended me sages gas checks.. I've never used that brand. 3) I use a push through lee sizer that fits a breech lock I use 309 and 311 for different applications 4) a reloading press I use a lee hand press and hold it upside down.

Do you have an appropriate sized expander to bell the case mouth to accept the bullet, and a crimping tool to close it (the case mouth)after seating the bullet, to aid feeding and chambering correctly?

I use a lee universal expander die.

https://www.titanreloading.com/product/universal-expanding-die/

https://www.titanreloading.com/product/lee-breech-lock-bullet-sizer-kit/

https://www.titanreloading.com/product/bl-311-bullet-sizer-and-punch/

https://www.titanreloading.com/product/bl-309-bullet-sizer-and-punch/
 

44 AMP

Staff
As already mentioned, you need a bullet made to take a gas check, one with a slightly reduced base to allow the gas check to be seated and "squeezed on" by the sizer die in a lubricator sizer I've done Lyman pistol slugs with Lyman tools, can't say about other brands.

Check the bullets you have, if they don't have the base to take a gas check, the point is moot.

Plain base bullets do fine, if they are the right hardness and you keep the velocity down. IF possible, ask the bullet maker what speed they recommend.
 

Shadow9mm

New member
So the process goes as follows, gas checks are typically added during the bullet sizing process. Some people lube and size at the same time. If you are wanting to add gas check to an already sized and lubed bullet here is what I would recommend.

Get a bullet sizer the same size as your bullets. Here's the lee sizer you can add to your press as a die for about $20https://www.midwayusa.com/product/1018523537?pid=694226

As far as the checks themselves. Some bullets are designed to have gas checks, some are not. The ones that do have a ledge or shelf at the bottom that the check goes over. If not you will need the gas checks designed for plain base bullets. Plain base vas checks are generally made of aluminum instead of copper and are thinner.

Sages outdoors is a great place to get gas checks
Traditional gas checks https://www.sagesoutdoors.com/gas-checks/copper-gas-checks/
Plain base gas checks https://www.sagesoutdoors.com/gas-checks/plain-base-gas-checks/

Some other things to keep in mind. You may need to flare your case mouths so it does not shave load off the bullets. Lee makes a universal neck expander for about $15 https://www.midwayusa.com/product/1011184394?pid=140461 To go along with that you will need some kind of crimp, if you dont have one built into your die, to un-flare the neck after seating.

if you dont already have one a set of micrometers might come in handy when measuring bullets. I have these and they work well.https://www.amazon.com/gp/product/B0045VKF5K/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
 

Marco Califo

New member
Yes, thanks. I found the Lee sizing stuff and have them in my cart at Midsouth. The bullets are Magnus 165 gr .309 RNFP. IIRC, Magnus said somewhere gas checks can be added. They are lubed and sized. So, I plan to pass them through the sizer only to seat the gas checks.
 

Marco Califo

New member
Plain base gas checks

Shadow9mm, those plain base gas checks look perfect for my purpose. Thanks. I sent a follow-up inquiry to Magnus.
I ordered the aluminum plain base. But the Lee 309 sizing die is out of stock everywhere.
 
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No special tools required. Just snap a check on a boolits base. When seating the cartridge with a FL Seating die that die will also crimp / tighten the gas check to its boolit too. The design of a gas check is to get the boolit down its barrel and out of without it's base lead being exposed to _flame cut. If the Gas Check happens to fall off during down range flight or slightly beyond muzzle end. No matter all's good.
 

mehavey

New member
When seating the cartridge with a FL Seating die that die will also crimp / tighten the gas check....
The OP is going to seat/crimp the gas check using the cartridge case's brass neck while seating ?
 

Recycled bullet

New member
No special tools required. Just snap a check on a boolits base. When seating the cartridge with a FL Seating die that die will also crimp / tighten the gas check to its boolit too. The design of a gas check is to get the boolit down its barrel and out of without it's base lead being exposed to _flame cut. If the Gas Check happens to fall off during down range flight or slightly beyond muzzle end. No matter all's good.
Hey sure shot McGee could you describe how that worked in your rifle?

Sometimes unsized bullets cause chambering issues due to the actual bullet diameter+ 2x the cartridge brass neck thickness is an interference fit in the guns firing chamber and the throat when chambering a loaded round.

This causes you to be unable to close the bolt and sometimes be unable to easily remove the cartridge from the chamber.
 

Marco Califo

New member
The OP is going to seat/crimp the gas check using the cartridge case's brass neck while seating ?
NO. OP did not say that. I am the OP. The Lee 309 sizing die is currently out of stock. I did order plain base gas checks. Magnus concurred with that.
 

Recycled bullet

New member
NO. OP did not say that. I am the OP. The Lee 309 sizing die is currently out of stock. I did order plain base gas checks. Magnus concurred with that.
Hey Marco Califo have you decided what propellant(s) to load under that bullet?

I have used IMR4227, IMR3031, Winchester AutoComp, Hodgdon Trail Boss, Alliant Red Dot,

probably others, that's just off the top of my head, under non gas checked powder coated or hitek coated bullets between 150-180 grain and shot

from bolt and lever action rifles chambered for 308 Winchester.

Pretty soon I'm going to find out if home made 208 grain cast hollow points will work 1-10" twist. They certainly do shoot well from 1-7" twist in 300 black out.

I think mehavy is trying to understand what sure shot McGee said.
 

Marco Califo

New member
Recycled Bullet. Where is that website that has them in stock? I can't read the image print.
Yes, I do have Lee breech lock equipment.
 

Recycled bullet

New member
Recycled Bullet. Where is that website that has them in stock? I can't read the image print.

Yes, I do have Lee breech lock equipment.
It's Titan Reloading. I listed links for the tools in post #2.

I have no idea if these tools work with plain base gas checks. I have never used plain based gas checks.
 

Marco Califo

New member
Ordered. I got one for 224 also, as I have a bunch of jacketed 223 that were spilled, walked on, and recovered. Should receive all in a week.
 
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Another technique is to use the P-wad (poly wad). Originally, these were just discs cut from a sheet of 0.063" LDPE with a sharpened case mouth. One is placed in the case mouth before seating the bullet. A drop of lube or hot melt glue can be put on it to hold it onto the bullet if the base is going to be seated below the bottom of the case neck. The plastic expands under pressure to make the gas seal, and the surface can absorb heat by melting if it comes to that. No additional sizing or fitting is required. They work fine, and zero-leading seems pretty typical. NECO used to sell fancy ones made from plastic with color layers so they were black on one and red on the other for consistently locating the more rounded edges the cutting tool produced. They also had nice little tools for seating them dead square in a case mouth. But the fancy ones weren't any cheaper than metal gas checks, which probably made it hard to compete, and they now seem to have been dropped from the catalog.
 

tangolima

New member
Another technique is to use the P-wad (poly wad). Originally, these were just discs cut from a sheet of 0.063" LDPE with a sharpened case mouth. One is placed in the case mouth before seating the bullet. A drop of lube or hot melt glue can be put on it to hold it onto the bullet if the base is going to be seated below the bottom of the case neck. The plastic expands under pressure to make the gas seal, and the surface can absorb heat by melting if it comes to that. No additional sizing or fitting is required. They work fine, and zero-leading seems pretty typical. NECO used to sell fancy ones made from plastic with color layers so they were black on one and red on the other for consistently locating the more rounded edges the cutting tool produced. They also had nice little tools for seating them dead square in a case mouth. But the fancy ones weren't any cheaper than metal gas checks, which probably made it hard to compete, and they now seem to have been dropped from the catalog.
I tried the home made version. It worked quite well. I was hoping it help my old krag digest the 500 rounds of bare base cast bullets. The plan fell through as the riflings were too worn to engage the lead. Had to go back to jacketed bullets.

The little discs will go help my low number 1903 to consume the bullets.

-TL

Sent from my SM-N960U using Tapatalk
 

Marco Califo

New member
Received Dies and Gas Checks

I received my orders. Put it together and tried to seat. Image #1 was with nose first, gas check over back-end of bullet, and pushed through the die. I think the gas checks went "inside-out". Not happy with that result.
So next, I tried gas check first, pushed through by the Flat-Point "round nose" which is quite flat. This got the better result in the next two photos. Lower bullet in #2 has the gas check seated, with the inside-out above it. Left bullet in #3 is gas check seated with regular bullet base to the right, showing color contrast (silver/grey).
So, "backwards" seems to be successful seating. Next Step will be to load up 20 and shoot in my Savage Axis II heavy 20" barrel with muzzle brake, and that will take a few days.

From Lyman 50:
"The 308 Winchester also works well with cast bullets. Best accuracy will usually occur in the velocity ranges of 1,600 to 2,000 feet per second."
All Lyman cast bullets used were gas-checked.
Lyman's load data for 170 cast using 15 grains of Unique, for 1816 fps. Similar loads using IMR-3031 or H335(WC844) go up to 26-2700 fps, but I can extrapolate down for 2000 fps. That is probably as fast as I will want these cast bullets to go. I am looking for a reduced-recoil range ammo (steel plates out to 400 yards), as that Savage has been beating my shoulder with Australian NATO 7.62 rounds. I located my jug of WC872, so I am sure duplex loads in 308 and 300 WM will be coming soon.
 

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