Remove the stock and you will see what is keeping the bolt from sliding out.
Simple as Pie. (or PI). Remove the buttplate screws and buttplate. Unscrew the buttstock Bolt, all the way, with a LONG screwdriver, remove the bolt and slide off the stock.
The Winchester model 70 is a bolt action sporting rifle. In 1936 Winchester introduced the bolt action rifle to the American Market. The model 70 was largely based on the Model 54.
To remove the firing pin from a Winchester Model 100, first ensure the firearm is unloaded and safe to handle. Disassemble the rifle by removing the stock and bolt assembly. Once the bolt is accessible, locate the firing pin retaining pin or screw, remove it, and gently slide out the firing pin from the bolt assembly. Reassemble the rifle by reversing the disassembly steps.
Best left to a gunsmith.
This bolt is the same one used in the Winchester model 57, 69 and 75 rifles.
Open the bolt, hold the trigger back, pull the bolt out
Winchester did not produce a Model 81 bolt action. Exactly how is your rifle marked? sales@countrygunsmith.net
remove the buttplate screws, and the buttplate. In the large round hole in the stock is the stock bolt. That is unscrewed to remove the stock from the rifle.
Numrich Gun Parts Corp would be your best bet in finding a bolt for your Winchester rifle.
70 $
Try e-gunparts.com