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Excerpt from Fouling Shot #158, Jul-Aug 2002.

By Forrest Asmus.

This past shooting season has been an enjoy able one for me. Our editor has encouraged me to write about the upside-down gas check idea which I have tried in my buffalo rifle with interesting and encouraging results. My rifle of choice this summer has been a Falling Block Works “J” action barreled up in .44/63 Ballard. I like this designation better than the better known .444Marlin since I shoot mainly in the “traditional” matches but it is in fact the .444 chambered on a 16-twist barrel.In the process of load development I settled on a custom made, lathe bored 460 grain Mos bullet, 19grains SR 4759, 1/4 sheet T/P and an unsized, inverted, Hornady gas check as “standard”. The inverted gas check idea came from CBA memberand my correspondent Mustafa Curtess. In one letter Mustafa told me how he had been trying the inverted gas checks (IGC) in his .45/70 with good results. I loaded some up in the .44/63 and tried them out too. My results were very good and I continued to shoot this combination right along even though Mustafa later indicated that his results had not proven consistent and he was putting the idea on hold. I wondered what had gone wrong with his procedures and kept on using them in my shooting. I was having excellent results with the upside down cups. Since this is a rather unusual utilization of a gascheck I’ll explain how I put them to use: The .44/63 case,being a straight sided design, allows me to seat the unsized IGC under the bullet without running the risk ofa check dropping off, as might be possible in a bottlenecked case. I start each check into the case about 0.060” by using a backed-off case expander punch. The IGC is then forced down as the bullet is seated on top of it, slightly compressing the column of powder and T/P.The procedure prevents the check from moving away from the base of the bullet during handling and transport. This tight stacking of components is very important in my view because if the check were to move away from the bullet base it would then become a projectile inside thecase upon firing. When it hit the base of a stationary bullet pressures would instantaneously rise, exceed the strength of the barrel steel and ring the chamber. I cautionany member who contemplates trying this loading method to use the utmost caution! From my point of view the IGC serves three purposes:It does seal the hot powder gases just as well as a normally seated check and certainly better than a card wad does. During firing the check also scrapes the bore, removing any lead wash which might otherwise accumulate during the firing of plain base bullets. Then, I believe that the unsized check, being forced into the case ahead of the soft lead bullet, acts like an expander punch, opening the case just a bit more and reducing the amount of bullet deformation I have seen on bullet bodies which were forced into undersize cases. (My cases are only partially sized, but excess case neck tensionis something we all know should be controlled to a bare minimum.)

I have used this load for shooting matches and for everyday sessions at our range here in Wyoming. Excellent consistent results have been my experience. In loading the IGC in my .45/70 I have found that any of the loads where I formerly used a 0.050 card wad under the bullet accept the use of a IGC without changing the load’s former dependability at all and improving accuracy as noted above. The advantages of not having to be concerned about lead fouling are considerable, both because it no longer happens, and because worry itself is eliminated. In all cases, accuracy is improved.

Greener developed the .310 cartridge in the early 1900’s as a target round. Shortly after the Australian Government identified the potential of the mild round for military training purposes and adopted it for ‘cadet’ musketry; hence the assumed name of “.310 Cadet”.

In line with the British tradition of naming cartridges relative to bore dimensions and not groove the Greener round has, as one might expect, a .310 bore with subsequent groove diameter of .318 and features a heel style bullet. Essentially it is an over grown .22RF and factory ammo I have dismantled featured a cupped based bullet to aid the sub diameter heel to slug up to groove dimensions and firm crimp; just like a .22RF. ‘Cartridges of the World’ list velocity for a 120gr bullet of 1530fps.

I was fortunate enough to be gifted a Wesley Richards Cadet with a brand new BSA barrel. All advice was that converted .32-20 brass would suffice for the little rifle however from day one I was not able to achieve any degree of accuracy with smokeless powders. Black powder duplex loads with a compressed main charge shot perfectly but accuracy with all manner of modern propellants remained elusive. Long story short, .32-20 brass neck wall thickness runs .007, bullet heels were .309 and the chamber measures .333 at the case mouth. Doing the sums I had .010 difference and upon ignition of the smokeless charges the case walls released allowing a massive blast of hot propellant gas to whistle by the unsupported heel canting the bullet, destroying accuracy and causing leading in exactly the way all under sized bullets do. The black powder duplex load shot well on the basis that BP as a propellant has different burning characteristics and upon ignition facilitates undersized bullets to expand to maximum allowable (slug up). That and a compressed charge of powder acting as a consumable over powder wad blocking any initial blast and keeping the bullet square to the bore. Original factory ammo, as mentioned already, featured a crimp and cupped base allowing the heel to expand and seal in the same way .22RF does however these features were not available to me.

Recently the club I belong to purchased, for member use, a case neck annealing machine. Manufactured and invented here in New Zealand the device operates by induction and is programmable for hundreds of different cartridge cases. Why anneal your brass case necks? As brass is worked by sizing and firing (contracting and expanding) the crystalline structure changes and it work hardens. This results in longitudinal splits in the neck rendering cases useless or inconsistency in neck tension (how tight the neck holds the bullet) leading to accuracy issues.

Annealing case necks has always been a black art on a good day. One popular method written about countless times over the years by numerous gunzine writers was to stand cases in water deep enough to come half way up the cartridge case body and heat the neck up to ‘cherry red’. The water acted as a heat sink and prevented the case head and body from becoming soft; desirable for the neck but detrimental to cartridge case integrity. As cases were annealed the recommended action was to knock them over into the water to cool. It transpired that the water was unnecessary as heating the necks to ‘cherry red’ was far too hot for the purpose and when heated to the correct temperature of approximately 700F with a butane torch the annealing takes place fast enough that the lower section of a cartridge case is not affected. With enough practice the technique is workable but in my experience far from consistent.

Some smart individual then realised that lead melts at 621F and when casting is best run at about 700F; the magic number for cartridge brass annealing. The idea was that cases held by the rim would have their necks dipped into the molten lead until the rim was uncomfortable to hold. Great in theory but the one time I tried it my cases end up with lead coated necks.

Another idea was to apply heat sensitive crayon as used in welding applications to the neck of the brass. Each colour is calibrated so by applying the crayon for 700F to the neck of the case upon it melting the correct temperature for annealing has been reached and heating can be stopped. Another great theory but who needs crayon on their cartridge brass and the work that goes with it?