I still have one. Homer fitted two insets for me. Back in the day when no one weighed their powders for short range benchrest, the Culver inserts were the golden standard.
I won the 1997 1000 yards iron sight prone and sling match with ammo loaded in the hotel room using the Lyman/Culver set up. Rifle was a 223 space gun built by my friend Bill Wylde (Wylde chamber fame) it was quite a feat for a gas gun to take the cheap wood considering the rest of the field were all magnums, Palma and a few 7mm match rifles.
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I gave the 2nd one to Bill. He machined a SS body for it. With his set up he won a few F Class matches in Canada just throwing charges. That was in the early stage of the F Class.
You be the judge on the quality of the Culver inserts. Then again, the operator throwing consistency is still the determinant.
I will be glad to send you the Lyman55 with the Culver, so you can take your own measurements. Send me an email if interested.
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