Plan: Prime railway rifle receiver

Plan: Prime railway rifle receiver is a weapon mod plan in Fallout 76.

Location

 * The scorchbeast queen will drop a random prime plan that has not already been learned by the player character. The chance of being awarded a specific plan is 1/(38 - count of prime plans already learned). Once the plan has been learned, it can no longer drop.
 * May also drop from regular scorchbeasts with 5% of the probability above.
 * Seasonal content:
 * 2019 Holiday Gifts
 * ATLAS donor's provisions
 * Has a low chance to be awarded from Supplying Demands, if the optional task to search for sunken valuables is completed.

Vendors
Not available at any in-game vendors.

Unlocks
The plan unlocks crafting of the prime receiver mod for the railway rifle at a weapons workbench. It also unlocks crafting of the following ammo types at a tinker's workbench if they have not already been learned:
 * Ultracite railway spike