Good thing to test also is see if you are already getting "full burn" with the current 24 inch. If you are then you are wasting money having a longer barrel put on. You would actually lose a little speed.
Good way to test is to take an OLD white sheet ( I say old in case your married..Dont wanna pee off the wife ,) ) Lay it on the ground longways toward target, get in the prone position with the end of the barrel about 2 inches from the end of the sheet, and about 6 inches up. Let a round loose and see if there is powder on the sheet. If there is then you could either reduce powder charge or longer barrel. If there isnt then the only need for a longer barrel is if you want to increase your powder charge with the same burn rate powder, or if you want to go with a possibly slower burn rate for more pressure. Some calibres do better with a slower charge while some like a faster burn. Its all dependant on the rifles and calibres.
One of the things I struggle with when afield is keeping my rifle clean and in good working order. Small amounts of dust and dirt collect moisture; moisture can freeze rendering your action immovable when you need it most. I have seen this happen on multiple occasions, and over time, I’ve learned the cause and how to prevent this from happening.
The first thing that you need to avoid before going afield is leaving excess oil on the gun. Oil will trap dirt and sand in all the wrong places....