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223 seating depth ?

I have a Tikka T3x varmint in 223. I loaded some 69 gr SMK's with 24.0 of Reloader 15 and mistakenly seated them 63 thousands off the lands, isn't that too much of a jump ? They do shoot into one 1/2 inch hole at 100 yds. I am wondering if less jump would be a little more accurate ? Does anyone have a recommendation about where to seat them ?

Also at 300 yds they shoot 2 1/2 " groups but drop 4". Should I use a little more powder at 300yds ?
 
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You should be fine on seating depth. I’ve got some Australian Outback factory ammo with that bullet and it is 75+ thousandths off in my rifle and it shoots decent.
 
Those bullets were designed to be jump tolerant due to being used in semi automatic platforms. The 77 is the same.
 
I have the same rifle in the same caliber - it's awesomely accurate. The vertical pistol grip and outstanding trigger no doubt are major contributors to my ability to shoot this rifle with a high degree of precision, at least for me.

The heaviest bullet I've shot out of mine is the 60 Vmax. I'm seating .030" off the lands and mine shoots sub 1/4 moa with H4895 and Federal 205M primers.

With regards to powder charge changes, I let the group size dictate the best powder charge not the amount of drop at a given distance.
 
If you have 8t maybe even a 9 twist try the 77 smk or 77gr.Tmk 24 grains of reloader 15 and yes they are jump tolerable I'm jumping 77 TMK 0.050"in my compass Lake engineering AR-15 24 in Krieger 8 twist. I'm using 23.5 grains of TAC powder Lake City brass CCI 400 primers half an inch at 100 yards easy. Shoots good clean-out out to 800 yards
 
I have a Savage Model 12 FCV
I'm shooting the 69gr Tipped Match Kings .013" from jam.
It consistently shoots <.5 moa
 
First handload I ever built was 223 Rem for an R700 VS. The county Rangemaster suggested I start with H335, 7-1/2 primer, and 53-gr SMK seated just touching the lands. Best groups I've shot to this day were with that load, but I was much younger and steadier behind the gun. Now all my loads, for various rifles, sport at least .020" of jump, for no compelling reason.
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I have a .223 Rem F-TR "practice rifle" I had built several years ago. At the time I ordered it, I did not reload. I started reloading for it some time well after I got it, and requested the reamer print, which told me the rifle had zero freebore. It shoots commercial 77 gr FGMM ammo very, very well. Just for kicks, I measured the distance to "touching" the other day with some 77 gr SMKs, then compared that to the COAL of loaded FGMM 77 ammo. According to the numbers I measured, the 77s in that ammo were jumping exactly .060". I was rather surprised to find that large of a jump with factory 77 SMK ammo as the rifle was chambered with zero freebore, but it shoots very well, so I have no complaints.

The reason for doing seating depth testing is to find the optimal seating depth window. Even if the load shoots well at .063" off the lands, that doesn't mean it is the optimal seating depth. Nonetheless, if the rifle shoots well with the 69 SMKs seated at .063" off the lands, it might be worth testing further with bullets seated to some distance on either side of that seating depth. Berger has a seating depth test protocol originally aimed at VLD bullets, which can sometimes be finicky with respect to seating depth. It is designed to cover a very wide range of seating depth regions, to find an area where precision is better than the other regions. In other words, it is a very coarse seating depth test so as to cover a wide area with minimal rounds fired as a first step toward optimizing seating depth. Of course, it is still wise to go back and cover the best region identified in smaller increments as the second step. You may have accidentally discover that your rifle likes the 69 SMKs seated well off the lands. Further testing will reveal whether that holds true. The rifle will always tell you where it wants to shoot with a particular load, but there is always the question of how much time, effort, and barrel life to put into seating depth testing, particularly if a given bullet doesn't seem to work well in the region between touching and about .030" off the lands commonly used as a typical seating depth test range.

 
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i would strongly urge you to do the following-

Go to the Berger website and see their recommendation to find the optimal seating depth for your chamber.

It will take 24 rounds during the first session in six bullet groups.

One will be a few thou off the lands, then .040 off the lands then .080, then .120 off. One of these will be a lot better than the others.

Take that one, say .040 off and do another 6 round test going up and down from that .040 off and see which one is best. Then the next session, use that number as a starting point and repeat going up and down from that number, and do it again the following session while narrowing down the spread. Make sure you use all identical brass with the same neck tension, etc. You will find the actual best seating depth in about 100 rounds.

I have a Savage F/TR from the factory. My best was about .060 off the lands. I have a Shilen replacement barrel and best is about .164 off the lands. Make sure you take good notes on your results and steps taken.

The first to know what is best is your target, then you and then hopefully, us.

Best of luck.
 
i would strongly urge you to do the following-

Go to the Berger website and see their recommendation to find the optimal seating depth for your chamber.

It will take 24 rounds during the first session in six bullet groups.

One will be a few thou off the lands, then .040 off the lands then .080, then .120 off. One of these will be a lot better than the others.

Take that one, say .040 off and do another 6 round test going up and down from that .040 off and see which one is best. Then the next session, use that number as a starting point and repeat going up and down from that number, and do it again the following session while narrowing down the spread. Make sure you use all identical brass with the same neck tension, etc. You will find the actual best seating depth in about 100 rounds.

I have a Savage F/TR from the factory. My best was about .060 off the lands. I have a Shilen replacement barrel and best is about .164 off the lands. Make sure you take good notes on your results and steps taken.

The first to know what is best is your target, then you and then hopefully, us.

Best of luck.

Seeing is believing. I did this Berger trial a while back when trying to salvage a load, and learned a long jump was best! Next time I develop a new load this will be my first step, before charge weight.
 
You’ve already have some good suggestion, but, if it were I, I would load them to mag length and test them. They should hammer at mag length, then if you can/want to single load, measure the distance to the lands and play with a jump and maybe find something spectacular.
My experience and guess would show that they will shoot pretty darn well from .010 off to mag length, whatever that may be. Your load listed looks pretty standard too.
I‘ve got lots of 69 SMK’s, one of my favorite bullets, they just work.
 
Thank you guys for all the help, I appreciate it
I think you can find nodes at any seating depth that print a ragged hole. You just have to test from where your at, moving forward or back .003 or .004 thou at a time a few times each way. Werther it be ,010 off the lands or .100 off the lands you can find nodes. Try it. It's all about barrel harmonics and bullet exit the barrel timing....HB
 
It’s a depth tolerant bullet. I seat mine to .020 off the lands in my Rem 700 and get .45” groups, so about the same as you’re getting. You just want to make sure they aren’t so deep to affect case capacity and pressure.
 
FWIW - commercial FGMM 77s are seated very close to .060" off the lands in a rifle I have with a .223 Rem Match chamber that has zero freebore. They shoot remarkably well. Any freebore length greater than zero would put the 77 SMKs loaded in this ammo correspondingly farther from the lands. FGMM77 match ammo seems to shoot very well across a wide range of different rifles; many of which I'm sure have freebore greater than zero. Your 69 SMKs might tune in a little tighter closer to the lands, then again, they might not. The only way to be sure is to do a seating depth test.
 

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