PistollPeet The print actually looks really good! There appears to be a gap between the front plates and the lower, which does indicate it's too short. Shrinkage is not going to be the issue, rather it is caused by the printers steps / mm being off a bit. Scaling the length of the lower in the slicer is the best fix, aside from calibrating steps / mm.
When calculating the the error, the take down and swivel pin should be used as a reference. There should be a 0.010" gap between the plates and the lower, anymore than this is due to the lower being too short. If the gap is 0.040", it means that there is an error of 0.040 - 0.010 = 0.030". The pins are 6.25" apart. The error ratio would be 0.030 / 6.25 = 0.0048 or 0.48%. Scaling the length axis (however you have it on the print bed) by 100.5% should fix the issue in this example.
