I have always had trouble controlling pick movement while strumming. Gripping tighter on a pick causes tension in my playing and I am wondering if anyone has some tips for me? Picks have always felt slippery to me even the ones that have rubber tops.
This is a common issue with lots of solutions available, not limited to:
-Picks with holes through them (These are very easy to make yourself, try a leather hole punch for thicker picks). Your fingers can touch each other through the hole, keeping the pick in place better. The star pattern here probably helps with pick rotation; perhaps you could achieve something similar with two holes instead of one.
-Picks with textured grip surfaces. You could also make this yourself with a bit of "grip tape" or just by scratching it up with coarse sandpaper. There are plenty of products in this category too.
-"Gorilla snot", rosin, or other tacky substances.
-Personally, dry hands make me lose grip, so any solution for dry skin may help.
-Thinner picks will flex to absorb some of the impact from the guitar string, keeping it from being knocked out your hand so easily.
@Edward provided an excellent answer based on things you can do to get a better grip. Without knowing how you play I would like to add that the issue may also be remedied with some adjustments to technique. Reducing the length of your strumming stroke by using less arm and more of a relaxed forearm and wrist rotation will help you maintain better control over the pick. Another thing to be mindful of is to make sure the pick starts out angled slightly upwards for down strums and vice versa. This will reduce the resistance of the strings against the pick which also helps in preventing the pick from shifting in your hand.
Grip (friction) depends on three things: how hard you press on the surface; the texture of the surface; and the area in contact. We don't want to change the first, because squeezing harder makes your wrist tighten up. It's also fairly hard to change the second by enough to make a difference, as demonstrated by you trying different types of picks but still having the same problem. So, the solution - use wider picks! You then have more contact area between the pick and your fingers, and more friction, without changing anything else.
There's also an effect where any off-centre force on the pick causes the pick to twist in your grip. Controlling this depends only on two things: how hard you grip; and how wide the pick is (because leverage). So again, the solution - use wider picks.
For me, Jim Dunlop triangle picks are the ideal solution here. Compared to other picks, these are wide enough to double the contact area, and hence double your grip. The point is still the right kind of angle (and there are versions with more or less pointy corners), so it doesn't affect your tone or technique. And in case that wasn't enough reason to prefer them, you also have three picking corners instead of just one, so they last three times as long. Winning at guitar picks!
Something not yet mentioned, many people start out holding the pick in the "upright heart" position with the pointed bit making contact with strings. If you rotate the pick 90 degrees so that the rounded side, instead, is making contact there will be less slippage. First, the total surface area of the pick in your fingers will be increased as it runs back along your thumb. Second, contact with the strings will be graded, less abrupt and therefore less apt to jar and slip. You will also get finer control this way, which is why so many flat-pickers use this technique. Good luck.
Without more information it's hard to know what you're encountering exactly, but here are some factors to consider.
When strumming a pick across the strings, as the pick crosses each string, the pick pulls the string somewhat until the string slides off the end of the pick, plucking it and allowing it to vibrate freely. During this movement of the pick across the string, the string gives somewhat, but so does the pick and so too do your fingers, slightly. The combination of all three of those "gives" are what allows the plucking to happen.
I personally find that I enjoy a more "soft" pick when strumming an acoustic, and a more "firm" pick when playing lead on an electric. This is because on the acoustic, the strings are thicker and have more tension, so they give less - therefore, the pick and your fingers will have to give more in order to achieve the same plucking of the strings.
So if you have a hard time holding onto the pick, it's likely that the tension of the strings and the hardness of the pick aren't enough to allow the plucking to happen, and you're having to compensate with your fingers. Even if you stiffen your hold, it's more tension on your fingers than it should be, and it would probably feel like you have to choose between breaking the strings or dropping the pick.
If this is acoustic, I personally recommend Dunlop 0.60mm nylon standard or max grip picks (the medium grey ones).
Where do your picks wear out? If they wear out on the edge rather than the very point of the pick, then you're digging too deep with your pick. If this is the case, practice air-picking like a hummingbird approaches a flower, gradually closer and closer to the string until you sound the string. Your pick should just kiss the string.
Just to throw this one into the mix…
I never use a pick at all on 6-string, occasionally on bass.
This has worked well for me for 35 years - however, I don't do 6 gigs a week. I can imagine running out of finger at that rate. As pretty much a studio-only player I find it gives me by far the best control.
I don't do much picking, mostly I do strumming, but I personally recommend the Dunlop Max-Grip nylon picks. Nylon lasts much longer than plastic, and the 3D texturing on these picks almost make them feel like they are sticking to my fingers with a light touch.