For what purpose do you want to exceed the SAAMI OAL specs? Accuracy? I don't think you'll see any significant improvement from the short barreled 1895g lever action Marlin by going over the specs. If you were talking about a single shot rifle, then yes, there might be some accuracy advantage to it without hampering other considerations.
With the 1895, you must consider the action type and recoil as an overriding factor in your reloading efforts.
I have an 1895GS on the way, but I don't have have it yet. However, I have reloaded for the .444 Marlin, and at this time, am reloading for a 336CB in 30/30.
I can tell you that the 336CB, which has the same 2.550" OAL SAAMI specs as the 45/70, has an OAL of 2.507" OAL, when seated to the cannelure of an Oregon Trail 165gr RNFP bullet. The same bullet, when seated to the lands, is 2.553". This gives a total of .046" leeway, or "freebore".....but, I only seat to the cannelure anyway. The only reason I have this information, is for curiosity's sake.....I wanted to know what the freebore was, using this particular bullet.
You might be able to move the bullet off the cannelure, but unless you're using a Lee factory crimp die, you'll not find the effort is worth it. Even if you do, you'll have to cycle different length OALs through the action to see if they'll cycle loaded cartridges properly.
All of the above boils down to this.....You can increase the OAL somewhat, but you're not likely to see any real advantage to it.
hog
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