Fundamentals is the key and the pre-requisite. And I would say "prone" is the default position to start with.
Good rifle, optic and ammo are also pre-requisites, at least good enough to get the results you are after. Sub 1 IPHY groups is the first goal, thenb .75 IPHY, then 0.50 IPHY. Some go for 0.25 IPHY.
You can shoot 30 cal at 100yds or .22LR at 50yds or even .22LR at 25yds. .22LR will test all aspects of fundamentals EXCEPT position. So, .22LR by itself is not sufficient to develop full range of fundamentals, though it will help with sight picture, trigger control and breathing.
I use 1/4 inch dots as targets for .22LR. Shoot a string of 30 quarter inch dots, one shot per dot. At 25yds you should be able to tag them all and center punch most of them. So .22LR can definitely be part of the program of developing fundamentals, but cannot be the entire program.
For 30 cal, you want a bolt gun. I won't get into debate about which one, that could be a separate thread
But a bolt gun removes some variables and you want to focus on fundamentals. The "shooter" part of the weapons system.
It is worth attending some training on position. It is difficult to view your position if you are you. I've tried using camera and tripods looking down at me and in extremis you can make that work, but its a PITA and the feedback cycle is longer. The key is to get "right behind the rifle" so your body will absorb the recoil, coming straight to the rear and not deviate the gun to the left or right as it recoils. So you have to be "right behind the rifle" ... and it is difficult for a person to judge if they are right behind the rifle or canted off to the side. That's where training and observer can help.
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And you are never done working on fundaments. This is a fine motor skill and ideally requires daily practice to maintain. I live on a cattle ranch, so I can shoot "in my backyard" every day ... and that's the goal, shoot a little every day ... like 20 rds per day ... that's FAR better than 100yds once per week as lots of rounds quickly can cause various issues like eye fatigue (looking through magnified optics a lot in a short time). So lots more rounds can introduce more variables. Maybe some can shoot 100+ rds with no sorts of fatigue, but I've learned to detect signs of eye fatigue in me and I stop at that point, though actually I design my sessions to avoid it.
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Once your fundamentals are showing improvement "up and to the right" ... and group average group sizes are falling consistently (I track every round and every group in a spreadsheet) ... then you will find other positions besides prone can be conquered. I shoot most of my rounds off RRS tripod, but I've been shooting off tripods for six years ... tripod shooting takes a BUNCH of practice and I wouldn't start there. I'd definitely start with prone.
And shoot the best ammo you can get. Remove that variable. For .22LR either ELEY or Center-X and shoot sub-sonic only. Unfortunately, these days, getting such ammo may be impossible. Shoot .22LR at 25yds at first maybe and once that gets boring then move to 50yds. You can get a "cheap" chinese scope, like an athlon to shoot at 25yds so it will parallax down to 25yds as that all you need it to do. You need to be able to zero at 25yds and parallax at 25yds. You don't need it to do anything else.
Otherwise, shoot the 30 cal rifle at 100yds.
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Its been a hecque of a journey for me learning HOW to develop and sustain fundamentals and I jumped into this thread because like the OP I had to do it by myself. I'm in rural area and we don't have people around here that do this. I did finally take a class that taught details on a good prone position and definitely recommend a class like that. I think the milestones on my journey were:
1 - Sight picture - finally being able to tell if I have a good sight picture through a rifle scope. Yes, looking for the shadows sounds easy, but for me "easy is hard" and it took at least a year. You also need to get really solid setting the diopter and the parallax. And don't assume anything is "easy". As at least for me "easy is hard"
2 - Trigger control - this one made the most difference to group size. Took me from 1.5 to .75 .. it was "magic" ... this can be taught, but for me I just stumbled into it by firing various different rifles. One of those (a crappy REM700 wally world gun) had a hogue stock on it and for whatever reason I was getting 0.64 avg IPHY groups with it. Eventually I figured out it was the way that stock made me pull the trigger that was causing the improvement. I translated that idea to all other guns and the improvement came along.
3 - Position - this one really didn't go to the next level until after the class I mentioned above. But you will eventually be able to tell whether you have a solid position and are behind the rifle ... and if you're shooting 30 cal+ you'll definitely be able to tell after you pull the trigger as well !!!
4 - Breath control - this one is still tough for me ... but then I have not prioritized it ... though ... though my results have gotten into the "good enuff for what I've trying to do" ... so I mostly really focus on consistency. Sustaining small groups across as many sets of conditions as possible. That's my focus now.
5 - Ammo - I didn't think it mattered so much, but when I switched from AMAX 168gr for 308 to FGMM 175gr for 308, my group sizes dropped from .75 to .50 with many groups being .33-ish ... though avg across all conditions remains 0.50-ish. But the lesson learned which that AMMO MATTERS. Not that you can buy fundamentals, but using good ammo rules out yet another variable. And "good" doesn't mean high MV. Good means smallest group size with your rifle.
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Well I've written too many words, but again the topic reasonates with me as I think I had the same questions as the OP nine years ago when I first started shooting scoped rifle
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My .22LR setups as of about a year ago
Top one is Tikka T1x with Althon 6-24x scope and center-x. The gun was $400-ish, the scope was $300-ish, chosen because it could parallax down to 10yds.
The bottom one is CMMG upper setup for night ratting. Using Eley HP.
