The Marlin 1870 is valued at a price close to $600 to $700. The exact will price will depend upon the condition of the rifle.
50-300 USD or so
It should be marked on the barrel if it has the Marlin micro groove rifling.The model 25m was made from 1989-2003.That being said it will if it was a early made rifle.
50-150 USD
100-400 USD depending on condition
My Glenfield Model 25 has a micro-groove barrel,so I imagine others do as well.
50-200
The Marlin Model 783, which features a Micro-Groove barrel, was produced exclusively from 1971 to 1980. This model was specifically designed for the .22 WMR (Winchester Magnum Rimfire) cartridge. After 1980, Marlin discontinued the production of the Model 783.
What is the value of a Marlin Micro Groove Barrel MCD 336 Cal 30-30 WIN?"
1300
Try a 1300 barrel
I have seen them sell for between 400-500 dollars depending on condition and a good bore.
Numrich gun parts Item #418800 D Key #28 $18.45 + shipping