"They are doing exactly what they should do! When you get any of the screw in heads that are actually glue ons but have an adapter in them, you will almost always need to heat and spin them on the adapters to get them true. The 150 screw-on is just a 125 glue on stuck on a short adapter with hot melt. Get yourself some 160's and put a long adapter in and you've got a 200 grainer. Add some steel adapters and you can easily get them up above 250. You're far better off to just buy the glue on to start with and then add your choice of adapter. All kinds of combo's to be had with the use of adapters and glue on heads."
Ah! That explains A LOT!
Thanks! I apologize to the folks at Magnus. In case they are reading: Would you be so kind as to add mention this fact on your packaging?
Anyway, before gluing it up with JB weld (thanks Ozy) I added some bird shot to the inside of the broadhead to where the now lead filled insert could go into, and with the glue it all adds up to 228 grains now.
The reason for posting this is just to satisfy the tinkerers and those who may have old broadheads laying around that they consider too light and may want to modify - or for guys like me who need to keep things on the cheap