Recent content by Scotchmo

When we used to hold GP matches at the Morro Bay course, we did not use general timers for everyone, even at the 2021 National, no timers. I always gave the threat of putting a timer on any squad that had empty lanes in front of them, and had squads backing up behind them. But usually not...

I go as far as .0005 to .001 under groove diameter. The lands will usually bulge/squeeze the lead out just enough to seal the groove areas.

Best that you make the distinction between lb weight and lbm. A slug is 32.17405 lbm. There are 7000 grains in a lbm. 7000 x 32.17405‎ = 225,218 There are 225,218 grains in a slug mass. So, either way you look at, when velocity is in fps and mass is grains, the kinetic energy formula: 1/2 x...

If we were on a planet with 1/2 the gravity of earth, would an airgun’s kinetic energy be 1/2 what it was on earth? Answer: no Muzzle energy of a projectile is kinetic energy and is not affected by gravity. I don’t need the acceleration of gravity to calculate kinetic energy. The kinetic...

I 3D printed a snug fitting holder for my talking timer and pellet box. They just happened to be the same dimensions. I look at the timer every time I grab a pellet. Gives me a good feel for time progress.

I’ve been using talking countdown timers in competition since 2015 when another competitor gave me one at an IHMSA match. Great for timed FT matches.

1:40 twist is intended for pellets. Unlikely that 1:40 will work well with slugs. Maybe try a very short (43gr?) conventional slug like NSA offers. Go with the faster twist for slugs.

What would the muzzle energy formula be if it were calculated in deep space, where there is no gravity? Ok. I already know the answer. And the actual muzzle energy is the same on the earth as it is in space, and gravity has nothing to do with it. If you use weight and the estimated acceleration...

A piston gun use the inertia of the piston to hold the compressed air forward momentarily before that piston is forced back (piston bounce) by the compressed air. Ideally, the projectile leaves the barrel before the piston reverses direction significantly, thereby maximizing use of the...

My similar Coltri had similar symptoms. It was at the connection on the end of the lower (4th stage) cylinder. I used a 1-1/6” open end wrench to snug it down. Leak stopped. A little bit of vapor out of the intake after shutting down is normal for mine.

In the living room. 0n the floor. If someone wants to try it: Practice in your living room. Try the yoga “easy pose”, and then lean forward to have your elbows on your knees. It’s a very stable position and it’s possible to be very relaxed. If you need it, have a stool/chair/couch near by to...

I have a Skout Epoch .30 and like it, but it does not have the juice for most .257 slugs.

If shooting Airguns at 100+ yards (even 200+ yds) .257 is a good option. .308 better than .30 for that purpose.

.257 ammunition is not really “costly”. You won’t save much, if any, with a .30 when compared to a .257. Cost is somewhat proportional to projectile weight. In order to save, you’ll need to stick with light pellets, so a .177 or .22 might be better if cost is a main consideration. $0.19 for NSA...