Board Thread:General Nerf discussion/@comment-27985798-20200527012131/@comment-27306930-20200614153734

Don't drill out anything. Cut the spring to the same length as the stock spring. Install it, reassemble and then test it. You might discover it works perfect.

If the performance is poor, then remove the ARs and their springs. Put some padding on the plunger head. Some felt, a silicone disk, or rubber washer work really well. Then reassemble and test it again.

But don't drill out anything right now. You might find it works better with the ARs installed. If you drill it out, that won't be an option.