223 seating depth from the lands?

[MildBill]

I have been working on loads for both my 223 and 223 ackley (both are Rem 700's in aluminum bedding block stocks and floated barrels. trying different bullets in the 50 to 60 grain range

I have been seating 0.030 off the lands.

The regular 223 is showing a trend of the first two bullets are very tight and the third is off from the other two 3/4 to 1 inch. at 100 yards. Groups are shot slow and methodical. the ackley has been more consistent with groups

Brass is all lake city and uniformed as far a primer pockets, and trimmed, all same year but not weight sorted.

Powder is Benchmark, charges are thrown a little light and trickled up with an RCBS 1010 scale.

loaded on a forster co-ax press with forster micrometer seating die, redding die for the ackley

Where do other folks start? Wondering if seating depth might tighten things up.

 

[Rick in Oregon]

Here's some targets shot during load development for my Cooper M21 VR in 223. Nuthin' spectacular, but definitely "minute of rat" seated just shy of the lands at .002":

My 223 Ackley does best right at .010" off the lands with 50gr NBT's. All loads done using Redding dies w/Comp seater.

 

[stinnett1981]

Seat them .005 off lands.

 

[bheadboy]

i found benchmark not to be a accurate as h4198 and 2015, seated .015 off with 50 gr Sierra bk. they were under .500 just starting loads

Bob

 

[areaone]

Just off the lands,.002-.005 at the most.

 

[stinnett1981]

53g Vmax 25g Benchmark .005 off lands is very accurate for mine

 

[40X Guy]

In your .223AI try XBR 8208 with a 55 BT seated about .050 off the lands. Same with the standard .223 and also try some H335. Lapua brass can't hurt either. I love the XBR in .223 class rifles.

Are you shooting custom barrels or factory barrels? Factory barrels may have a bunch of unnecessary freebore and its tough to seat them out to the lands as you may not have the bullet seated deep enough in the case neck.

As far as seating depth, if you think you are close with one of your loads, try going in or out in .005 increments and shoot some groups. Or you could also try an OCW test to find your charge weight, then do the seating depth test last to tighten them up.

Frank

 

[MildBill]

thanks for all of the feedback.

they are factory barrels.

 

[bumtownbutch]

I'm shooting a 223AI built by Speedy Gonzales. I experimented with my most accurate load of XBR8208 and seating depth of touching, 0.005" off, 0.010" off, 0.015" off, and 0.020" off. The greatest accuracy and velocity occurred with the seating depth 0.010" off the lands. Hope this helps.

 

[Shynloco]

MildBill,
Just saw your post so I'm a bit late in getting into this discussion. And not to throw a monkey wrench into what others have written. But over the years, I've read and seen your question posted and discussed over and over again. And this is certainly not to say any of the suggestions others wrote are wrong or won't work. But the one thing I've found from personal testing time and time again with different rifles, what works in one rifle will not necessarily work in another, even if they are of the same caliber and made by the same manufacturer. Bottom line is that each particular rifle will tell you what she likes and what she doesn't like. That's why you must test by seating the bullet in .010 increments from all the way back to all the way into the the lands. Once you see the groups start coming together in a nice group, that when you want to break into seating by .005 depths. Even the same caliber bullets made by different manufacturers can make a huge difference when you are seeking ultimate accuracy for your particular rifle. Just my thoughts and not saying the others ideas are wrong.

 

[MildBill]

Sounds like what I might need to do is run my current loads that look promising over the chrono to look for small variation and then perhaps try adjusting seating depth to see if they tighten up?

Perhaps also do the same with the powder weight loads on either side of them?

 

[pacificman]

In two of my rifles that produced flyers I tried a different powder in one and different primers in the other to eliminate the flyers. I then play with bullet seating to see group change. That is what has worked for me. I had one rifle where I changed to same weight bullet but different brand and things improved. bullet seating was always last resort for me and I have found that most of my rifles seem to like at least a 20 to 30 thousands jump. My .204 will shoot .5 100 yard groups and the jump is .113 from the lands...go figure! Just my 2 cents worth. when you do get your rifle dialed in let us know what you found.

 

[mac86951]

To be honest, it will depend on each lot and bullet. I assume you sort your bullet by Ogive length and check weight?

My seating depth procedure is thus: Starting with a good load of powder, I'll then seat to touching the lands.

I'll carefully try jamming it 0.005, but rarely is this an improvement for my rifles, most VLD bullets like a little jump.
From touching the lands, I'll re-do ladder/group testing in 0.005 increments all the way to 0.04 off the lands.

My 7mmSAUM likes Berger 180s, but they really like to jump 0.025" My .223 with 80gr SMK likes 0.005"
You can then find your "window" and work within that for maximum consistency.

Once I've got the jump down, I then adjust the powder again...
Then back to the jump... etc... After 2 iterations it usually becomes a good load.

-Mac