Are there 26" long barrels commonly availabe for Springfield M1A ?

[Hammer]

Are there match grade 26" long barrels commonly available for the Springfield M1A ?

Am not including flash suppressor or muzzle brake.

 

[Doug Beach]

I’ve never seen or heard of one. The gas system would probably have to be completely redesigned.

 

[Heman]

Are there match grade 26" long barrels commonly available for the Springfield M1A ?

Am not including flash suppressor or muzzle brake.

The answer is no not common and "probably" never has been. The standard barrel length was dictated by USGI specifications and that became the length for service rifle rules and thus nobody has made one.
Gas system would work as is as that doesn't depend on the muzzle like the M1. Your iron sight clicks would be off. However the issue would be that is an awful thin barrel once you clear the stock and you make it 26" and there is going to be more whipping around, and it would change the adjustments on the rear sight.
If you want a 26" gas gun just go AR10.

 

[Doug Beach]

You wouldn’t pick up all that much velocity anyway. With 155gr bullets, a 30” barrel is only ~150fps faster than a 22”. A 26” splits the difference. Maybe 100 fps.