Please correct my thinking here .....

[Digger]

On the learning curve here with my Garand ....(long curve by the way )
Using IMR 4895 ... working up loads .....with different bollits ... my version of the famous gun is a "tanker" or shorty in .308 .
no one gun is the same but all the logic applied with different burning rates , boolit weights and all combined with the gas action timing ....would it not stand to reason the same load that works good in a standard length model , would by reasoning be not right as far as the shorter length barrel ?
Taking into account the timing from chamber to gas port ? ... aka ..less grains per rd. , faster powder etc. ?
or am i thinking to much into this .....

[Larry Gibson]

With the shorter barrel and thus shorter distance to the gas port on your tanker the gas port psi will be higher than on a standard length barrel, given the same load.

If you are using a cast bullet load of 4895 just at functional reliability in the standard barrel then the increase in gas port psi with the shorter barrel will still be under the maximum allowable. In other words with cast bullet loads using 4895 you are over thinking the problem.....because there is no problem.......

Larry Gibson

[Digger]

Once again , thank you Mr. Gibson ,, not the first time I have been "over thinking" a process ..
Since I have no chrono , to guesstimate by the action , accuracy is the only "tell" ..
One of the clues is whereabouts the shells get ejected , starting out some landed behind me , as I progressed , the were landing at about 1:00 or 2:00 o clock in front , accuracy has picked up ...
Using the new Ruger american has been distracting ...been trying out some IMR 4831 in it , so the temptation was there to use in the Tanker ..
Every thing functioned fine , the brass landing out front but the pressure was on the light side as the shells came out with quite a bit of blow back around the neck ...yet the brass landing out front ..clue ?
Got me to wondering about that very thing as the powder is on the slow side.

[Scharfschuetze]

When shooting the M-14 and M1A in National Match competition, I used a ported gas plug at times to minimize the gas cylinder pressure. I've also seen such gas plugs in use for the M1 Garand and for those worried about bending op rods or just reducing the stress on one, one of these would be of help.

Link: http://www.midwayusa.com/product/777146/schuster-dcm-adjustable-gas-plug-with-wrench-m1-garand-steel-parkerized

Of course as Larry points out, cast boolits shouldn't be cause for any concern.

[jonk]

Yes, you are dangerous, send me all your guns and ammo, I'll dispose of them properly. :)

As has been said: cast in a Garand of any type with reduced loads just isn't an issue pressure wise.

Now if you go with J-words, I'd back off the max load a grain or two.