Likely, friend, you will get your best accuracy with the Lee-Enfield rifle with flatbase bullets. Both the Hornady and the less expensive Sierra ro-Hunter are made this way.

I am shooting the Sierra Pro-Hunter 180 ahead of 38 grains of 4895, seating to the OAL of a Ball round. MV is 2250, accuracy is just fine.

With the Hornady 150 flatbase, I am usng 40 grains of 4064, seating so the ntire cannelure shows. Again, not a hot load but a very accurate one.

That 5-groove rifling does mak a difference. Try sticking a Ball round in the muzzle untilit meets the lands, then give it a gentle twist, remove and mike the mark on the bullet. That will tell you what the bore diameter is at the muzzle. The flatbase bullets, kicked hard enough on their little tail ends, tend to swell in the bore before they start moving, taking up some excess diameter. Boat-tails don't do this as well, which i why you stick with the flatbase slugs.

Most important of all: have fun!

And welcome to the club!
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