Some clarification.
In the picture with the 2 breechplugs, the one on the right is a standard Savage plug. The one on the left is for a custom 45 Savage that I built. That rifle has no barrel nut, that is why it can be so short, and it does NOT work in a standard Savage.
My theories behind the modified plug that Grouse is using are:
1) better ignition since the powder is closer to the primer;
2) longer vent liner life since the volume behind the vent liner is smaller;
3) longer vent liner life since the area behind the vent liner fills with carbon faster, decreasing the volume & some carbon is deposited inside of the vent liner from the primer which needs to be worn off by the combustion gasses before the steel is eroded;
4) slight increase in velocity due to an effective increase in the barrel length.
My original was adding a steel drill bushing into my Savage breechplug as shown here ( RED is the drill bushing White is carbon crud ):
I used this for about 350 shots of very high doses of Lil'Gun and I actually had to clean the carbon from the inside of the bushing because the ID was getting smaller which reduced velocity. I then sent this to another shooter who used it for several hundred more shots. I eventually removed the bushing to test the design that Grouse is using since I felt that a standard vent liner may work too.
edge.
