should i go with a 3x9 or a 4x12 scope for my lr .308 ap4. the longest shot i will be takeing is about 350 to 400 yards.i'll be shooting wild hogs and deer.

I think a 3-9 is plenty for an AP4.

I bought a 2.5-10x42 for my LR-308B. I like that the 2.5 allows for close in quick target acquisition. I have never needed more than 9 power for any White Tail out to 400 yards.

You may want to consider a mildot scope and or a range finder to determine the distance and holdover for that range. My LR-308B shoots within +/- 4 inches of center from 0 to 300 yards with a 250 yard zero with Federal P308F. But at 350 yards it is 10 inches low and 17.7 at 400 so it is important to get the distance right beyond 300 yards. A heavier bullet would also help with the bullet drop but I do not think the 16" AP4 barrel is appropriate for the heavy bullet.

4x12 IMHO. 4x is a nice medium range magnification, and the 12x will help with the longer range precision.

I'd go with a 4.5X14 Nikon Buckmaster SF with a mil dot. Cost is under $300 and you will really like the versatility. I've got 3 I use and 2 6 18 SF.

Greg

I prefer to use a lower magnification for hunting. Most adjustable scopes will reduce light transmission when cranked up to a high magnification. Considering most shots while hunting take place in the early morning and at dusk this will put you at a dissadvantage.
For years I used fixed scopes in 4 and 6x on my hunting rifles and never had trouble with kill shots out to 300yds.
I have a couple guns set up with 2x7 and 3x9 and have no issues at all, but I rarely crank the power up when hunting mostly due to not having any time to do so.
I think a 3x9 is a good compromise scope for hunting. Just remenber to leave it at the lowest possible setting for the un-expected close range shots. It would be next to impossible to hit a deer at 40 to 50 yards with your optic set at 9x but no problem at all if it is on 3.
Just my opinion.