I got six, my bud targeted them exclusively and got his limit (12).
As far as digging advice goes - if you know which kind of clam you want to dig up, you should focus on that. Since I had a couple of novice diggers with me, we didn't really focus, it was more "See that hole? Dig it up and see what is in there."
we were carrying a mix of clam guns and shovels. For gapers, I wouldn't bother with the gun - it works well enough for the butters and softshells, but the larger gapers tend to be deeper than the gun can get and not tear up your back lifting the sand out.
*edited to add*
As far as digging for Gapers goes
I've tried shovel and gun. This is only the second time that I have gone digging for clams, so I am sure folks who have been doing this a while can chime in. but, in the two outings thus far, I have learned a few things.
The ODFW page on Gapers gives a hint at how to prevent the hole you are digging from collapsing - cut the bottom off of a 5 gallon bucket and drive it in the sand around the show. Haven't tried it yet, but I can see how that would be helpful, having had most of the holes I dug for gapers collapse in on my arm - nothing like being stuck with your hand around clam buried in wet sand above your elbow. Another idea that I have yet to try is to take a small diameter dowel and follow the neck down as it retracts. This is supposed to give the digger an approximation on the direction the clam body is in relation to the neck. If you find a show with the tip of the neck still at the top, you may even be able to figure out how deep the clam is.
Keep you bounty on you. I dug up a gaper that was bigger than my fist, neck was over a foot long. I stuffed it in my bag, laid the bag down and started digging. Within five minutes the seagulls had looted my bag, and had bitten off half of the necks of the gapers that I dug up. At that point the birds were lucky I didn't have a .22 on me.
On my next run out I plan on doing a little bit better organizing with my gear. Trying to carry a shovel, a clam gun, a bucket and a bag full of clams with sore and tired arms, while covered in sand, is pretty draining.
So, if I cut the bottom of the bucket off, I am going to bolt some strapping to it to use as a sling to carry it in, and strap the gun and shovel to it as well. I will twist tie the dowel onto the shovel handle.
The image is of the Netarts bay map, and the yellow circle is the general location of where I was digging for Gapers.
Cheers,
Madoc