I have used bumper boy throwers for 3 years or so and have been limited in the distance I can use them at because the dogs don't see them. They come out so fast that they will also miss some reasonably short square marks. These problems go away if LARGE flages are used. These slow down the bumper and flap to make them very visable out to 350. The point of this part is to share a source of excellent material to make the flags. Farmtek www.FarmTek.com , sells a material that is white on one side and black on the other. I bought 50' of the 2' wide material for 33 cents a running foot.(cc2946 is the cat num). I make my Flags 4 inches by 2 feet. Fold up the end and ad a groumet. If you hook one to a hand thrown bumper it makes a sound sort of like a pheasent tak9ing off, at least thats what my dogs say is the reason they leave. I've also found that hooking them to a hand thrown bumper not only makes them more visable but if you have a training partner like mine who likes to throw all bumper 70 yards it restricts the distance they can throw.
My young dogs have quit runing at the guns because they can see the flag on the ground.

Also, I bought a 209 blank pistol from sportsmans guide and have shot about 300 rounds thru it. It seems quite well made, not at all like the "cheap" one I finally threw away. Costs about $50 for a club member. www.sportsmansguide.com , search for blank pistol. 209 is shotgun primers,cheaper than 22 blanks.

Thanks Steve! Hopefully I'll get training this year. I'm moving to the Portland, Oregon area early this summer.

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Portland is a swell place. I'm going there to judge at the end of the month. Last year 187 people in portland fell off thier bikes and drowned.
If you don't understand that you will.
steve