Hey Bach~seeing "your holes" at 100 yards is part magnification, part scope quality. A decent scope in about the 14-16x range will do it. A crappy scope in the 18x (and up) will accomplish the same with more eye fatigue and a side order of regret.
Kidding aside, on the lower end of the scale I like the Mueller APT. I have one on my .22WMR. Biggish scope, but that 30mm tube lets in allot of light;
http://www.whitefalls.ca/Descriptions/APT4.5-14x40mmmb.html
The Hawke Varmint SF scopes have a great reputation for quality/value, but I've never owned one. Tried to, my local dealer wanted too much for one. I DID just buy a Vortex Crossfire II and think it's a VERY nice scope for the money. Mine is a 4-12x40 AO with the BDC reticle, but they offer it in a 6-18x44 AO, a scope I'll be looking at seriously if I get back into the HMR scene again.
http://vortexcanada.net/products/riflescopes/crossfire2/crossfire2_6-18x44ao_bdc.html
If Vortex would make they're Crossfire IIs with side focus, I'd be very happy but for the price, I'm impressed with mine so far. Comparable quality to my Vortex Viper HS.