You should be able to get it out. If your blade makes it all the way through the target then you could take your broadhead off then pull it out with hurting your target more. If it doesn't go all the way through then make sure you dont twist your arrow when you pull out. Try pulling as straight as you can so your blades are coming out in the same path they went in.
For the most part I only use my 4x4 Block for broadheads. I use my 3-d's for practice tips. Actually the broadheads pull out easier than the field points do.
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Muzzy practice broadheads are all I shoot. They weigh/fly/impact exactly the same as the actual broadhead. I never shoot field points because I don't hunt with them. I do go through a new target each year though.
Like previously mentioned, pull the arrow straight out of the target. And yes, if the arrow comes out the back of the target, which is often the case, unscrew the head then pull the shaft out. This will add life to your target.
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'07 Hoyt Vectrix XL 50-60# / maxed at 63# 30"
HHA OL-5000 single pin
Wisker Biscuit
KWIKEE KWIVER / XX75-2314 arrows
S-Coil stabilizer / Loop & Kisser / Fletcher Peep
TRU FIRE / Hurricane Release
Muzzy 3 blade 100gr