Marlin is one of the sponsors of US biathlon, and the Marlin 2000 is in common use as a club Biathlon rifle, when equipped with the Summer Biathlon kit (see the exploded diagram at the bottom of this page for part numbers). Though not as nice as an Anshutz, they are substantially cheaper, and will certainly hit the target if you have good technique, and take take good care of them.
Over the years, I have found that there are a few problems that keep cropping up, and a couple of things that you can do to enhance the performance of this rifle:
If you have trouble ejecting themagazine with gloves on, mill and install a slightly longer clip release button (See the inset in the exploded figure below, item B).
If the rifle tends to jam alot because the magazine goes too far up, disassemble the rifle and inspect the magazine guide - see the exploded diagram at the bottom of the page, and Figure 1. The guide is made of plastic, and the pivot pin end of that guide tends to crack.
If you maintain a set of the marlin rifles, maintain a record of which rifles have misfires. If you get a lot of misfires, the firing pin may need to be replaced.
If you maintain several Marlins, and pull the bolt on the rifles - for transportation for instance, record the numbers of the bolts - it is hand marked on the body of the bolt - it is usually pretty faint, and note which rifle serial number it goes with. We have found from hard exerience that the bolts are sometimes NOT interchangeable between rifles. You will have to call Marlin to get the correspondence between rifle serial number and bolt serial number.
If you are zeroeing a a rifle, and you can't get the group to move in the direction you want, check to see if the set screw on the rear sight is preventing motion. This screw is very thin, and I personally have overlooked this screw for several years.
Do not overtighten the bedding screw - it looks like it is fairly easy to strip out.
If you need to order parts, this is an exploded diagram of the Marlin. Click on the image to expand the view.
If you have hints or tips on Marlin rifles you feel belong here, drop me a line: firstname.lastname@example.org