I am going to put a barrel band sling attachment on my heavy barreled 223. It’s a 26” with a moderator and putting a sling on the stock forend doesn’t work as the rifle will tend to fall backwards. I appreciate that when shooting you won’t be able to use the sling as a shooting aid and you need to make sure it doesn’t add pressure on the barrel. Is there any reason why I shouldn’t go down this route.

In my experience and opinion there is no substitute for a barrel sling mount. The rifle carries straight up and down. On the stock it always causes the rifle to arc back and I don't like the feel of it.

No.

You could try a different kind of sling.

I use the so-called Safari Sling, which leaves a rifle horizontal against your hip. It would be pretty useless on an actual safari, pointing at the PH's back most of the time, but is great for hunting on your own.

It keeps the rifle instantly available, even when you glass with both hands or 'strain the potatoes'.

IMO barrel band slings are for hunting rifles and mostly big bores and thats the only way to go, as they serve to carry only..

If you intend to wrap up in a target sling it will move you point of impact unless perhaps your barrel is a very heavy target barrel, and thats still a maybe..but Im sure your aware of that..

I don't understand why you can't position them somehow in the wood even with metal grip stop??

Have you given any thought to the all leather sling that half hitches on the barrel to a detachable sling or wrap (optional) in the butt, they are used with shotguns and even double rifles and work real well..and you can carry one in your pocket if you wish.