I shot my first deer 17 years ago with a .223 and have always had a probably unreasonable enthusiasm for it. It seems to work well even with 55gr size bullets but there is a lot more potential if using heavier bullets. Factory rifles are a bit limiting for the best possible results with the longer 75-90gr bullets mainly due to restrictive mag length now that 1:8 twists are more available. Aftermarket mags like the AICS pattern accurate mags can be modified easily to allow about 70mm OAL, 10-15mm more than most .223 factory mags. This is a more modern and geeky approach than the spirit of the ol' .222 with factory 55 grainers but it does extend the capability of a .223 by miles, to within spitting distance of standard factory .243 maybe but for half the powder. 80gr at 2850 from an 18" barrel.
I like my custom model 7 and haven't taken another rifle out of the safe in the last 6 months but have only been out 4 times and shot 4 deer with it so far.
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