The next ENGC 3-Gun match is going to be in October, and it'll be four stages--one pistol, one rifle, one shotgun, and one a combined pistol/shotgun stage.
We are playing with some ideas for multigun rules, so the pistol/shotgun stage will be scored separately from the other three stages.
When I started, I used a Glock 34, Rem 870, and a Bushmaster Shorty AK-version AR-15, all with iron sights---and did just fine. If it shoots, you can play with the rest of the kids.
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(I still use two out of those three guns for matches.)
Pistol stage will probably be around 30-32 rounds, Shotgun about 20-30 birdshot (7 1/2 or 8 shot work just fine), and Rifle around 35-45. Combined stage (this time) will need about 12 shotgun shells (birdshot) and 12 pistol rounds. Total, I'd bring about 100 rounds of each type, just in case of re-shoots and such. (You won't shoot them all, but I've never lost a match because I brought too much ammo.
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)
The Eastern Nebraska Practical Shooters have a Facebook page where we post stuff periodically (including our new proposed multigun rules in the discussion section there) and also a website at
www.easternnebraskapracticalshooters.com as someone has already mentioned.
If you have other questions, feel free to PM me, since (for my sins) I am the 3-Gun coordinator for ENPS.