whynow? Are you shooting your own loads? Out of magazine?

I have two friends I shoot with both have 1/7 16" carbines. One is a DI the other is a piston. They both seem to top out on 69grn. All factory ammo though

I didn't want to quote Mr Farknocker's post as it is quite large. But to continue with his comments I have found with my reloading and my guns very small amounts of change when using 0.1gr increments. No matter how hard I try I cannot rest my gun steady enough to see a lot of difference.

Speaking of resting your gun...How do you rest your gun when testing loads? What I do for rifles is to rest the stock on a sand bag and prop the buttstock on a sand bag to eliminate the need for user input as far as the position of the rifle is concerned.The rifle is free to move back and forth with the recoil.  I do not shoulder the rifle nor place my left hand (i'm a right handed shooter) on any part of the rifle. If at all possible, I do not place my cheek on the cheek weld and limit the contact of my trigger hand to the trigger only. This is an awkward way of firing the gun but I find that once the rifle is set up pointing toward zero, there's no shaking of the rifle at all. The thinking here is that the less user input there is, the less chance of error there is and the more consistent the shots will be. The results are consistent and I've gotten good results with this technique but I'm not sure if this technique is the best way to go. For one thing, this is not how I normally shoot. Second, I'm aware of the role harmonics play in testing loads so if the rifle is not engaged in the manner that it's intended to be shot when loads are tested, the rifle may shoot differently when the rifle is actually held and shot the way it was intended to be shot. How do you fire your rifles when testing your loads?

Speaking of resting your gun...How do you rest your gun when testing loads? What I do for rifles is to rest the stock on a sand bag and prop the buttstock on a sand bag to eliminate the need for user input as far as the position of the rifle is concerned.The rifle is free to move back and forth with the recoil.  I do not shoulder the rifle nor place my left hand (i'm a right handed shooter) on any part of the rifle. If at all possible, I do not place my cheek on the cheek weld and limit the contact of my trigger hand to the trigger only. This is an awkward way of firing the gun but I find that once the rifle is set up pointing toward zero, there's no shaking of the rifle at all. The thinking here is that the less user input there is, the less chance of error there is and the more consistent the shots will be. The results are consistent and I've gotten good results with this technique but I'm not sure if this technique is the best way to go. For one thing, this is not how I normally shoot. Second, I'm aware of the role harmonics play in testing loads so if the rifle is not engaged in the manner that it's intended to be shot when loads are tested, the rifle may shoot differently when the rifle is actually held and shot the way it was intended to be shot. How do you fire your rifles when testing your loads?

I do something similar to you. I use a Harris Bipod on the front. Harris Bipods are quite stable. I have not found another bipod as solid and stiff as a Harris. I bring some wood shims to put under one of the feet if the rifle needs leveling. Some benches are pretty good but others are terrible. I have a nice Protektor leather sand bag with ears I bought off eBay. The ears fit the contour of my stock pretty good. I move the bag back and forth to get sighted in vertically. I place my shoulder close but not touching the stock. I don't touch the stock with my left hand. I try not to put any undo pressure in any direction on the stock. I do try and place a light cheek weld. Take a deep breath and let half of it out and slowly squeeze the trigger. Hopefully not on a windy day. I don't know if this is the right or wrong way to do it. I just know it works pretty well as I get pretty consistent shots. I am aware of the harmonics of the barrel being different depending on how the rifle is shot. All I do after I choose a load is I sight in the scope to POA. I have not noticed much of a difference at 100yds due to different dynamics though I am sure it will make a huge difference at longer distances. I have a slightly different approach for my AR's as I found it didn't make much difference how I held it steady. As long as it is steady.

I could be wrong but I think consistency is more important than form. If you can be consistent doing it your way then that is the correct way to do it. I guess I could buy a Led Sled but it is more more thing to carry and I am not sure it is worth it for me at this time.

whynow? Are you shooting your own loads? Out of magazine?

I have two friends I shoot with both have 1/7 16" carbines. One is a DI the other is a piston. They both seem to top out on 69grn. All factory ammo though

I have shot my reloads of 77SMK from a 1/8 AR loaded thru NHMTG and Colt mags and fed/fired properly.   I try to aim for 2.250" but due to differences in the Sierra bullet tip (above the ogive)  I get from 2.247" to 2.252" in my reloads.
Before loading my own, I fired factory Hornady 75gr. BTHP and Fed Premium 77 SMK with no issues.   Also before making live rounds, I made some dummies and they cycled thru the 1/8 then proceeded to load actual rounds.
I have not fired my reloads or tried my dummy rounds with similar COL thru the 1/7 AR yet, which is why I said I'll try later on. 
 I did not know that anything over 69 gr. will not feed properly  in 16" 1/7 carbines or midlengths.
I'll try to cycle the dummy rounds thru the 16" to see.  If they hang up then will just stick to the 1/8 upper.   Just started reloading for the .223 so I move slowly and ask questions to learn.

These loads especially the RL15 powder data are tried and have produced excellent results from my experience.
http://www.whiteoakprecision.com/info-reloading.htm

I have read many great results with 77 SMKs with 24.0 RL15, LC cases and with a Rem 7 1/2 primer. It is my benchmark load. I've tried over and under this load with no appreciable gains. I always come back to this load. I have had many close cleans at 200 and 300 yards - if I can only shoot it better. I've used 1x7 and 1x8 barrels Wilsons cut by White Oak - same results - flash hider or without - same. I have a Shilen 1x7 barrel that I have next in line to rebarrel, maybe for Camp Perry this year?! I don;t expect anything less.

Our club has a practice day at Puuloa this Sunday - welcome to try out your loads at 200 yards and beyond. For more info check out the events section or www.puuloa.com

I am entering late into this thread, but I think that interjecting OCW method of load development will save you a lot of time and money when you are looking for a good load.  You can use this process to find an optimum charge, then fine tune to your OCDs desire.  It has worked for me for many years and uses the least amount of powder, components, and range trips.  Also to add the proceedure has been proven to me in match and competition.   Any errors in shooting are produced by me.  I am that confident in the load and this particular load devolopment process.

whynow? Are you shooting your own loads? Out of magazine?

I have two friends I shoot with both have 1/7 16" carbines. One is a DI the other is a piston. They both seem to top out on 69grn. All factory ammo though

Today tested my dummy 77 SMK rounds on a BCM 16" midlength and a LE6920 carbine gas length 16".   Used a Colt, Magpul, NHMTG, DH and Center Ind. mags.  Dummies were all between 2.248" and 2.252" with one at 2.254".   They all were checked in a Wilson case gage and all cases trimmed to 1.750".  All dummies fit in mags, functioned properly, went in battery, ejected and fed next round in the BCM and LE6920.  Only for the DH mag took little more effort to load for some reason.
After the test I re-measured the COL and most dummies had increase of .004" and one was at 2.269" (rechecked with 2 calipers).   As said never noticed any problems so I don't know when that dummy went to 2.269".  Manuals list the max for mag length at 2.260".  Later although the tip touching the side I was able to load into the Colt mag.  I might be wrong but think that after cycling each dummy 10 times  maybe inertia pulled the bullet out like using a bullet puller.   ALL were FL sized and seated with the same dies and I used a factory Fed Premium round to set the seating die to get in the ballpark.   Don't know if this is a good method but was recommended on several articles.  None of my dummies or live rounds were crimped just neck tension.  Maybe need to look into a very light crimp although no cannelure.   Trying to get some with cannelure to try out.

Also I noticed after testing that all bullets had scratches or small nicks.  Don't know if this is normal for amount of times cycling or this may be a warning of headspace? issues.
This test only shows that the dummies cycled properly and I don't know if my reloads or factory ammo will do the same but I'll try it later at the range.  Right now I'm using it for the BCM 18" upper with rifle length gas system and have shot about 80 reloads with it.   As stated I'm a novice reloader and welcome any improvements or criticism to what I'm doing.  Safety first over a bruised ego if I'm doing wrong.   Only reason why I started reloading 77 SMK was not wanting to pay $30 a box of 20.

Bushido, what kind of issues did your friends have ?  Later I also plan to try some 69 SMK.

These loads especially the RL15 powder data are tried and have produced excellent results from my experience.
http://www.whiteoakprecision.com/info-reloading.htm

Our club has a practice day at Puuloa this Sunday - welcome to try out your loads at 200 yards and beyond. For more info check out the events section or www.puuloa.com

Ren, don't know if directed to me or all commenters but thanks for the offer.

whynow? I've read that the heavier longer bullets may have difficulty feeding out of some AR mags. I was just wondering if yours were experiencing the same.

My friends ARs, both 1/7s, just didn't seem to shoot the 75s well. Seems to like 68s and 69s. They haven't had the chance to shoot many brands yet. I bought a box of PPU 75grn from WGS for $17/20. They shot really good in my rifle. I went back and bought a few more boxes. I will let them try a few of those.

Heavies, found a long read about OCW. Will read when I have time. Thank you as well as all who have replied.

All the variables you are experimenting with have been done before with the 77 SMKs. no crimp or crimp = no difference. I tried seating them out to touch the lands once at 600 yards and found nothing different. Seat at mag length, dumped 24.0 RL15 in a Remington 71/2 primed case - done. I then go shoot. All that is done on a Dillon 550. I cut my cases with a Giraud TriWay and sized it before with a RCBS XDie on a Lee press. Nothing special. Shoots like Black Hills ammo.
If you are chasing benchrest results - then have at it. If you are looking at trying VLDs then you have a lot to play with, but with 77 SMKs the loads are pretty much proven by shooters with a lot of interest in results.

whynow? I've read that the heavier longer bullets may have difficulty feeding out of some AR mags. I was just wondering if yours were experiencing the same.

My friends ARs, both 1/7s, just didn't seem to shoot the 75s well. Seems to like 68s and 69s. They haven't had the chance to shoot many brands yet. I bought a box of PPU 75grn from WGS for $17/20. They shot really good in my rifle. I went back and bought a few more boxes. I will let them try a few of those.

I thought you meant anything over 69 gr. rounds did not cycle in your friends ARs, my bad.  The Lyman manual has longer than mag length OAL for 80 gr HPBT, 75 gr. Hornady A-max and there maybe others. 
Is the PPU round dirty or not bad?  That sounds like a decent price for 75 gr. .223, better than $30/box of 20.

If you are chasing benchrest results - then have at it. If you are looking at trying VLDs then you have a lot to play with, but with 77 SMKs the loads are pretty much proven by shooters with a lot of interest in results.

Basically I'm just  trying to get the best results using 77 gr. SMK with the powder I got .   
Will probably just stick to Sierra MK instead of trying VLD type.  Thanks.

I thought you meant anything over 69 gr. rounds did not cycle in your friends ARs, my bad.  The Lyman manual has longer than mag length OAL for 80 gr HPBT, 75 gr. Hornady A-max and there maybe others. 
Is the PPU round dirty or not bad?  That sounds like a decent price for 75 gr. .223, better than $30/box of 20.

Sorry about that. Reading my post I can see how that was comprehended. Both are fairly new guns to the owners so they are still seeing what it likes. I shoot a bolt gun in a AICS style DBM so depending on which magazine I choose, my COAL can be very generous feeding out of the magazine.

I didn't notice any abnormal carbon or copper buildiup with the PPU. That's "Match grade" ammo too. I was surprised at how well it shot our of my riffle. He had some reloaded 80grns but passed on those,

Basically I'm just  trying to get the best results using 77 gr. SMK with the powder I got .   
Will probably just stick to Sierra MK instead of trying VLD type.  Thanks.

Any particular reason? I've read good things about SMKs and VLDs. I just haven't got a chance to try the VLDs

Any particular reason? I've read good things about SMKs and VLDs. I just haven't got a chance to try the VLDs

The only reason for me is I"m new to reloading and don't want to get confused about getting into a lot of different things.   That's the way I look at it and take my time and in no rush since I retired.  People probably get fantastic results with VLD bullets and they have many good reviews.
 Some have long lengths and I only have semi auto .223/5.56 rifles and don't plan on getting a bolt rifle in .223.  I use a 3X9X40 scope and don't plan on long range stuff.  Things may change later but as Larry Potterfield says " and that's the way it is".
So to answer your question it's how I see things nothing wrong with VLD bullets.  Good luck.