RIght now I am 6'1" and weight 245, when I drop to kneeling position i cant keep all my weight on my right foot for more than a couple seconds which leads to massive shaking of the reticle. should I wait until i've lost some weight to practice kneeling or is this something eveyone encounters at first. Or should I practice anyway knowing i'll suck just to work on technique (or is this a waste of time since I can't get a stable platform).

also, what's a good group size for kneeling at 50 or 100 yards using a 6X optic, 14.5 cold hammer forged bcm barrel, 55 gr plinking ammo...I feel like i'm forgetting something else

Which kneeling position are you using?  I have no trouble sitting on my foot while it is rotated flat on the ground.  However, many others cannot do that and have to sit on their heel.  With sitting on the heel, you might try using a kneeling roll to support the ankle.

Also, identify where it hurts.  Is it in your muscles,  a point pressure on your butt or foot, or is it a bone pain.  Muscles may need to be stretched, while the other sorts, need to have positions varied to reduce the pain.

when I sit on my right foot my thigh begins to hurt as if it's being overstretched or there is to much weight being put on it, I can hold the position for maybe 5-10 seconds before the pain sets in. this causes instability to the degree that i'm no better kneeling than standing. Is there a way to reduce that pain which cause instability or do I need to lose weight. My goal is to achieve a stable firing position, as a marksman as a whole I want to be master shooting

There is not only one 'correct' kneeling position.  There are many variations, including those with the 'wrong' knee forward.  Do some more research and experiment, and perhaps do some yoga.

If something hurts and you can’t explain why, you should consult with a sports medicine doctor or orthopedist.  What you’re describing could be tight muscles, tight tendons, or another issue relating to poor circulation.  Poor circulation in a leg can be from cholesterol, being overweight with insufficient muscle to protect the vessels from being restricted, deep vein thrombosis, or another medical problem.  If you have shaking included, that is another issue that may be endemic of a bigger problem.  Or you’re just out of shape and need to continue to get in shape.  BUT, don’t just let this go without figuring out why it’s happening.  If you leave it alone and don’t address it, it can get progressively worse as you age to the point where it can cause more issues.

I don't know your age but if like me in your early 60's knelling can be a problem. I wear  a decent quality knee brace, mine is from Dr. Shock. This not only pads your knee from whatever  terrain you are on but helps give support when standing up. Amazon has the best selection and prices.

Try kneeling on BOTH knees.

For every 1 pound of weight you lose you take 4 pounds of pressure off your knees. Trust me, weight loss and exercise work wonders for the body. And a daily 30 minute brisk walk too.

Lots of great advice here: yoga, walks, both knees, lose weight, etc. Many of us are no longer icons of fitness as we get older or whatever. But merely posting here shows you are willing to do the work.

I've been to a lot of shooting courses and very surprised when i found one with a fitness requirement. I realized that fitness is integral to safety in a dynamic situation while at that class. And although I'm not in the shape i used to be, at least i passed the test and took the course.
https://maxvelocitytactical.com/videos/mvt-functional-fitness-assessment/

Definitely listen to your body. Know the difference between exertion discomfort versus pain. Gout in my big toe (I'm 50+ years old) won't let me do lunges properly. But i modify the angle of my foot and get them done. I think something similar is mentioned somewhere in the video.

I've done courses there too and was also surprised by the fitness requirement, but it helped get me in gear to focus on training for this type of work and after taking classes there I'm really glad that they have it.


For the OP, I have somewhat similar issues. If I'm kneeling and 'on toe', I can only hold it for a few minutes or I cramp up, but if, like another poster suggested, I rotate and 'sit on' my ankle, I can last longer. Depending on how long I'm in that position, I'll often rotate between the two methods. The big thing for me is to ensure that I'm 'on toe' prior to having to get up and move to the next position of cover. Personally, I've been trying to work on this issue by working on that position at home and doing alternating kneels with my gear and rifle on. I've got pretty stiff ankles from a lifetime of running (which really interferes with swimming, but that's a different story!) so I'm also trying to sit on my ankles a bit every night to try to loosen them up. Hope that helps!

Kneeling unsupported is kind of a niche shooting position.

If you don't have cover, go prone or move to cover.

If you fire while kneeling, you probably have cover or some sort of barricade to rest the rifle on.

I can see a non tactical or drill related reason to do it, but it shouldn't really be for an extended period of time

If you're just doing it to get good at it then just keep doing it. Your body will naturally adapt to it and improve

Stretch your quads and see how you feel.

Pat Mac likes "modified kneeling position" ... which is the squat position.  John Mosby also prefers the squat position.  I prefer it as well and it is faster to get into the squat position, but you have to be able to squat and balance.

I'm 5'-10" x 165 pounds and very fit (I complete a 4 mile x 15 minute ruck every other morning while carrying a 72# pack, cycle, lift, eat very healthy, etc) but can't "rice paddy prone" (or "dump squat" as I like to think of it) to save my life.  I just can't do it. I've learned to use other positions that are more natural and comfortable for me.  Continue to work on your fitness and find positions that feel natural to you.  

Regarding accuracy based upon my own shooting experience / ability (read: this is a hobbyist's opinion) a strong side unsupported (kneeling) group at 100 yards using a quality 6x optic and 2MOA plinking ammo should yield 4-5MOA for an experienced shooter or maybe 6-8 MOA for an inexperienced shooter.  For reference, I shoot A LOT (3x a week / 15,000rds a year).  From an improvised rest I shoot 5rds of Wolf steel case into around 1.25"  to 1.5" at 50yds using a 2MOA Aimpoint.  This is semi rapid fire.  When I use better ammo (still cheap but better .. e.g. PMC Bronze) the groups shrink to less than an inch excluding a 5th round flyer (I usually drop 4 on top of one another but always pull a single flyer that opens the group up).  From a kneeling position my groups usually about double.  A lot has to do with cross wind.  My range gets a lot of full value wind perpendicular to the direction of fire.  The wind on the rifle causes it to "feel" less stable.  I'm fighting gravity, muscles and wind on my hold.

ETA: I'm older (Nixon was President when I was born) and my eyes are starting have a detrimental effect on my shooting ability. I have started to migrate to LPVO with higher magnification than my old magnified standbys (ACOGs) in an attempt to overcome increasingly poor vision.

Another thought about your kneeling position technique.  Make sure your off-hand elbow is planted firmly against your offhand knee.

GOOD TECHNIQUE




BAD TECHNIQUE

What you are calling bad technique is just a non-braced kneeling position.  (Speed kneeling). You know, for making yourself a smaller target, getting behind cover, etc.  Throw a “cover” barrel in front of that shooter and that photo would make a lot more sense.

Braced techniques stabilize you so you can shoot more accurately.  Additionally it makes you a smaller target, and sometimes you find cover at just the right height so it also works with that.  

Non-braced techniques are to help you survive the gunfight.  You can just kneel like normal but maintain a taller profile, go down on both knees, or even put the strong knee up and push around the side of cover (seems backward at first, but works well).  Non-braced accuracy is basically the same as how you would do while just standing.  



And actually I will go even further and say that photo #2 shows a bad technique- elbow into a leg muscle.  Not great, kind of wobbly.  I prefer to push the elbow in front of the knee like photo #1 if possible.  If not, then I like to slide the elbow inward so you have muscle to muscle contact, so some stability, but not elbow into the muscle like in photo 2.  (It is just the most wobbly way to do it in my experience.)

What is your purpose and goal?

Are you looking to shoot matches or take a course that requires kneeling?  Military match rules often specify kneeling or squatting.  Sitting is also a separate position.

What group size are YOU looking to shoot?  B-27 or military EIC X-ring?  5-ring on an M9 target?  A hit anywhere?  Are you shooting against time?

We can't necessarily recommend one position over another without knowing your level of fitness and flexibility.  6'1" and 245 could be a college football player or semi-retired postman that needs to cut some donut holes out of his coffee break.