True arrow speed vs IBO Ratings

[CardiacArrest]

I know that the IBO rating is not the actual speed with a 350 to 400 grain hunting shaft and broadhead but I am unable to shoot through a chronograph and would like some opinions and estimations on how fast my hoyt supertec is shooting. The IBO is 330fps at 70#. However im shooting it on 65# with a 385 grain arrow. How fast do you think its really shooting? This is my back up bow I currently shoot a Ross Cardiac IBO 320 it has beenshot throughthe chronograph and shoots 285fps with a 385 grain shaft on 70#. Im just trying to compare the two so I can get them as close as possible.

[TFOX]

Probably a little over 300 fps at 30" draw.

[CardiacArrest]

ok thanks Im shooting a 29 inch draw but that probably wouldnt change much

[TFOX]

In that case,almost 300 fps.

[OHbowhntr]

Minus 5-10 for what is one your string, minus another 10 for the 1 inch under 30" on DL, and minus 15-17 for a 400 grain arrow, you're gonna be above 290, but probably a little below 300.