Our extended 45 inch 12 ga. magazine springs will work with almost any legth tube extension. Some trimming may be required for the best performance.
We recommend starting with the following lengths of spring extending past the end of the magazine tube as a starting point:
Springs can be trimmed down in 1 inch increments to fine tune the magazine spring for function. After trimming the spring to length, turn both ends down and in, so as not to bind with the magazine tube cap or follower.