I would buy 20 rounds, not a case at this point. Years ago the IMI 168 gr. equivalent did not have adequate case neck tension and a total lack of waterproofing between the case neck and the bullet. This led to "telescoping" of the bullet back into the case during feeding in semi-auto rifles. Get the 20 rounds, number them and record their OAL and then allow them to chamber dynamically between firing less expensive ammo. Remove the chambered IMI round and re-measure the OAL.