@Dogchapman7
It definitely takes some tension to hold the bells in the rack for double KB front squats (one of my favorite drills), but I can't say I've experienced particularly extreme forearm pump.
I'm having trouble visualizing how you hold the bells, but here's how I do it:
-- I keep my hands pretty close together, but I don't clasp my hands. The handles of the KBs are basically parallel to each other.
--My upper arms and elbow are in tight to my torso.
--As much as possible I try to keep my elbows under the center of mass of the bell.
--I try to maintain the same locked down rack, with elbows under the bells throughout the ROM, without lifting the elbows away from my body.
But in my experience, the key to holding the bells in the rack is less how you hold the bells per se, and more how your overall squat form allows you to hold the bells. I don't know if this is an issue for you, but it's a common problem for a lot of people learning the KB DFSQ.
You have to drop your hips down between your heels, with your knees moving forward over your toes, so you can keep your torso vertical, and you have to keep your chest up and T-spine extended.
This lets you keep your arms locked down tight to your torso, and your elbows under the bells. The rack position should not move much or at all during the lift. You should be able to keep your upper arms locked down and elbows under the bells throughout.
I think about driving my traps up and back throughout the lift, but especially out of the hole, to maintain a good extended upper back and keep myself in good position to maintain a solid rack.
If you try to sit back into the squat, with shins too vertical, instead of dropping your hips down, your torso will incline forward and you will have to fight to keep from dumping the bells forward out of the rack. If you can't keep your T-spine extended, you will also have to fight to keep from dumping the bells forward out of the rack. This entails having to lift your elbows out away from your body to the front and/or to the side (like flapping wings), and requires a lot more muscle power to hold the rack.
From your description, I can't really tell if any of this applies to you, but I find that keeping my torso as upright as possible is the biggest key to keeping a solid rack throughout a DFSQ.
Hope this helps.