Welcome to the forum! Sounds like quite a challenge. When you say 1/4" requirement, is that a consistent 1/4" or it did it one time? How many shots in the 1/4"group?
My goal is a consistent 1/4" average, which means not all groups are 1/4" because of the human factor.
The Creedmoor group of .1064" happened once, probably never again, however other groups have been less than 1/4". The pic shows 4 in one hole, with the third shot outside, at 100 yards. The recipe I found on a forum somewhere...143g Hornady ELD-X, 41.2g of H4350, OAL 2.82".
(BTW, my last 2 groups averaged .1550".)
Here's the gun...a Savage 12FV, 26" barrel, Boyd stock, bottom metal with 10 round mag, Athlon Ares ETR, 4.5-30x56 FFP, MOA, 34mm tube. (The old stock is in the foreground.)
My 25-06 is at .2868", with 87g Speer TNT, 58.4g of H1000. Next up will be 87g Speer Hot Core with 58g of H4831, if weather holds out.
My 6x45 stands at .4548". 'Work in progress'.