What is the difference between a recurve and a semi-recurve?

A semi-recurve is just that...the limbs are partially recurved in stead of fully. It's an old term from the 50s-60s that's no longer used. Today, they're call hybrid longbows.

I'll dig up a vid of Johnny Carson shooting a semi-recurve Bear Polar in the late 50s. Notice that the string doesn't touch the limb when braced.

I wish I could see them side by side, strung and unstrung. One thing is for sure, that doesn't look like my recurve.

Yep.

Great Clip - Sponsored by Winston, and shooting an apple off someone's head on TV. Yes sir, the times have changed!

FWIW I did own one of those Polars for a while, nothing special to me and I sold it.

The other thing I should mention is that on a semi-recurve like the Bear Polar or a modern hybrid longbow the limbs are narrower and thicker than on a recurve. They are also usually 'trapped' which means they are trapezoids in their shape.

I've got a 1955 Polar and it's exceedingly quiet and pretty snappy, with a fast flight type string. With a b50 string it's fairly sluggish.

Think those old tips will hold up to a FF string? Some guys have good luck with it, others have broken bows with the vintage stuff.

I shoot my selfbows with no stretch material padded at the tips. However some of those old bows don't have tips designed as well as my selfbows. I wouldn't use a thin endless loop with a hard serving but I wouldn't fear a good flemish twist padded well at the tips. Just use at least 9 grains per pound of arrow weight on those older bows. I would be more concerned about a too light arrow than a good non stretch string.

As long as the string grooves aren't too sharp and shaped decently, I think the risk of catastrophic failure on any vintage bow due to the use of FF strings is very low.

A lot of people advocate padding the loops with B50, but I doubt it's even necessary as long as they're thick enough so as to not start sawing into the limb.

It's pretty amazing how those old bows shoot with a decent string. I'd put my '64 Kodiak up against any modern recurve and come out just fine....and yes I own a pro-chrono and use it.

Agreed. I am mostly concerned about padded flemish lops when string groves look like notches cut into a thin flat limb.

It was not cutting it was the lack of stretch in the string that hurt old bows. The string absorbed energy. New material doesn't.