Every wipe, I tell myself that I am going to play sniper to reach level 7 or 9 to be able to buy M61 bullets and the grenade launcher, and maybe try getting the Kappa container, but every raid I forget that I hate those bolt action pieces of crap rifles. So this time, I've looked into a solution to level up Sniper Rifles skill, without actually playing them. And it turns out, it's actually pretty simple.
Sniper rifle and other weapon skills are levelled up by:
The important bit is that you gain skill experience by reloading the guns. For rifles with magazines, reloading from one mag to another over and over again works, and for a mosin, since it ejects one bullet to start reloading you can juste take a mosin at 4/5 bullets to start with a stack of ammo in your pockets. Then, simple: Just press R over and over again.
You can track the progression of your skill in the Skill page. At the beginning of the raid you will see a blue arrow pointing up, this means you gain 129% more experience for this skill. After reloading a bunch of times, you'll gain skill points and then the arrow will disappear, you now gain 100% skill XP. Keep reloading and you'll then see a red arrow pointing down, this means you now only gain 50% of the skill XP. It is now much slower to level up the skill, so you can give it a rest for 3 minutes at least. After 3 minutes you will still have a penalty but you'll still gain 75% skill XP.
The technique
So, the technique is simple: In addition to your normal gear, take as secondary weapon a sniper rifle and an extra magazine (or a stack of bullets for the Mosin) and when you're safe somewhere, spam R to relad to use all of your 129% and 100% skill XP gain (about 30 reloads). Once you've used them forget about it and go about your business. If it has been more than 3 minutes and you're in a safe place again give it a few reloads to use the 75% skill experience level gain. Once you used your 75% XP gain and are back at 50%, give it a rest for another 3 minutes. You can repeat this last step over and over again.
I personally use the VPO-215 since it's cheap and readily available (18585 roubles, Jaeger LL1).
This technique, just using the 129% and 100% skill XP gain will give you about 5 skill points per raid, more if you use the 75% XP gain now and then during the raid. In other words, it would take 2 raids to level up Sniper skills level 1, 4 raids for level 2, 6 raids for level 3, and so on until reaching level 10 after which it would take 20 raids per level until reaching elite level (although I just want to use this technique to reach the levels required for the quests).
Since the weapon is cheap you can just throw it away when you want to loot a good secondary weapon, or insure it to have it come back for later or resale. Otherwise you could just put it in your backpack, since it only takes 1×5 slots (a basic Daypack, Berkut, Scav backpack or anything bigger than that will take it).
Hopefully this is useful to others.
See you in raid, and don't forget your VPO.
PS: If you actually enjoy playing sniper rifles then you can simply play them but reload over and over again when you're safe to gain skill even faster.