understanding the lands

[Olde Man]

I was doing a seating depth test for my dasher with 107 vld's and ran into a problem. I couldn't set my Wilson seater die with the vld stem to give me consistent results. Long story short I measured base to ogive with the stoney point 243 insert and then the 22 insert, a 20 or 17 cal would be better, and subtracted the two measurements. From bullet lot to lot I measured .014 difference. I also measured a .003 difference with in the same lot. The seater stem contact point to ogive varied making it impossible to get consistent seating results. My solution was to seat the bullets .030 long and then measure each round from base to ogive and adjust the seater to achieve the desired depth. ES ended up around 3 to 5 and I was a happy camper.

 

[Ledd Slinger]

I was doing a seating depth test for my dasher with 107 vld's and ran into a problem. I couldn't set my Wilson seater die with the vld stem to give me consistent results. Long story short I measured base to ogive with the stoney point 243 insert and then the 22 insert, a 20 or 17 cal would be better, and subtracted the two measurements. From bullet lot to lot I measured .014 difference. I also measured a .003 difference with in the same lot. The seater stem contact point to ogive varied making it impossible to get consistent seating results. My solution was to seat the bullets .030 long and then measure each round from base to ogive and adjust the seater to achieve the desired depth. ES ended up around 3 to 5 and I was a happy camper.

I believe this where the advantage would would be found in a custom seating die from 21st Century. With 1/4" of contact surface on ogive to seating plug, the seating depth inconsistencies caused by the ogive variations you speak of would most likely all be negated. Plus the die seats the bullet with a pressure point much closer to the lands contact point.

 

[Rich S]

Would there be any advantage to making a comparitor with a chamber reamer and barrel stub? At least initially it would be a close duplication of the barrel.

Could one make a custom seater by drilling the seating stem, fill it with devcon and mate it to a bullet then drill a recess for the tip? It would be custom for each bullet type.

 

[Richard Coody]

Would there be any advantage to making a comparitor with a chamber reamer and barrel stub? At least initially it would be a close duplication of the barrel.

Could one make a custom seater by drilling the seating stem, fill it with devcon and mate it to a bullet then drill a recess for the tip? It would be custom for each bullet type.

the barrel stub comparator is already made. Great idea to start with if it is chambered exactly the same as the barrel. but it won't last as the barrel wears.

making a custom seater sounds like a great idea but it will only be perfect for 1 bullet. the problem with consistency in seating depth is not usually with the seater but variations in the curve of the ogive of the bullet. sorting can help and so can buying bullets with known consistency.

 

[Ledd Slinger]

Would there be any advantage to making a comparitor with a chamber reamer and barrel stub? At least initially it would be a close duplication of the barrel.

Could one make a custom seater by drilling the seating stem, fill it with devcon and mate it to a bullet then drill a recess for the tip? It would be custom for each bullet type.

That's exactly what I was thinking with the seater die when i was pondering how John mates his custom seater plug to customer provided bullets. I just came on this thread to post the devcon idea until I read your post. Beat me to it! Lol

I think that's an excellent idea. I have a coulple spare plugs for some rifles and am planning on trying it myself. The only things I would add is that you should probably use tight neck tension and ensure concentricity of the bullet being used and runout on the round is perfect before bedding the plug.

 

[fyrewall]

Would there be any advantage to making a comparitor with a chamber reamer and barrel stub? At least initially it would be a close duplication of the barrel.

Could one make a custom seater by drilling the seating stem, fill it with devcon and mate it to a bullet then drill a recess for the tip? It would be custom for each bullet type.

going along with LeddSlinger - seater modifications

Sounds like a good idea, epoxy is used for many bedding applications and this might be one of them. Be sure to grip the bullet securely in the case and check for run out. Without expanding, I would be sure I did not stick a bullet inside of the stem, possibly the forming round might have the bullet securely glued in with epoxy and the bullet coated with some non bumpy release agent.

I have drilled out a number of my seater stems so tips would not contact the bottom of the seater stem. I was unable to drill out the bottom of some of my hard tool steel stems using a normal hardware store drill so another drill other than the usual variety might be needed. Possibly, no drilling would be needed.

 

[Richard Coody]

i have never had a problem with a seater stem. Now i only use forster, redding and wilson seater dies. for a threaded die i think the forster is best but i almost exclusively use the wilson seaters with an arbor press these days.

The way i see it only 2 things can cause inconsistent seating depth.

first is where the seater stem contacts the curve of the ogive of the bullet. If this curve is consistent throughout a group of bullets then they should all seat to the same dimension. even if some bullets are longer base to ogive if the relationship of the curve and contact point with the ogive and seater stem is the same the overall length of the cartridge should remain consistent. Some bullets might be seated deeper but base to ogive should remain the same. Bullet consistency is the key here.

second is neck tension. without consistent neck tension seating effort will vary considerably. with my neck turned and annealed every firing 6BR brass when i seat bullets with my 21st century shooting hydro press i can expect neck tension to be very consistent. seated bullets are usually right on the money and never vary more than .001.

i have found from experience as brass work hardens neck tension consistency goes right out the window. Makes consistent bullet seating much more difficult. Another example is that all important shoulder bump. Ever notice with new brass you can easily get a nice 1 to 2 thousandths shoulder bump but as the brass work hardens you start chasing that bump. Of course annealing cures that problem. Same way with bullet seating. If you want to see what i am talking about take some of that brass you are having inconsistent bullet seating and buy or borrow an arbor press with a force indicator and see how wide a range of seating force you have.

 

[Just Dave]

Alright guys, Either I'm doing it wrong ? Or there is something different about a stock 700 action that Alex left out of the video.. I tried his method on two different rifles yesterday, and could not get the "click" he refers to.. Stripped down, the bolt falls as he said, but as soon as I add case ( under extractor) there is resistance to close the bolt.. It doesn't flop like in the video.. I can push it down firmly, but on upstroke it lifts freely, but I had to tap the handle to pull seated bullet out.. Did i miss something ? , Does this trick only work on custom actions ? The measurements I came up with, so that bolt would close, and not require a slap to open were different by .150" versus my cheap Hornady comparator..

 

[lpreddick]

Alright guys, Either I'm doing it wrong ? Or there is something different about a stock 700 action that Alex left out of the video.. I tried his method on two different rifles yesterday, and could not get the "click" he refers to.. Stripped down, the bolt falls as he said, but as soon as I add case ( under extractor) there is resistance to close the bolt.. It doesn't flop like in the video.. I can push it down firmly, but on upstroke it lifts freely, but I had to tap the handle to pull seated bullet out.. Did i miss something ? , Does this trick only work on custom actions ? The measurements I came up with, so that bolt would close, and not require a slap to open were different by .150" versus my cheap Hornady comparator..

Resistance to bolt closure...need to push shoulder back until bolt falls. I had a problem doing this with brass that had been fired hot... case just forward of extraction groove was not getting sized...used a small base body die and bolt fell.

 

[Ledd Slinger]

Alright guys, Either I'm doing it wrong ? Or there is something different about a stock 700 action that Alex left out of the video.. I tried his method on two different rifles yesterday, and could not get the "click" he refers to.. Stripped down, the bolt falls as he said, but as soon as I add case ( under extractor) there is resistance to close the bolt.. It doesn't flop like in the video.. I can push it down firmly, but on upstroke it lifts freely, but I had to tap the handle to pull seated bullet out.. Did i miss something ? , Does this trick only work on custom actions ? The measurements I came up with, so that bolt would close, and not require a slap to open were different by .150" versus my cheap Hornady comparator..

Sounds like a brass headspace or body sizing issue. Makes sure the brass closes and ejects from the chamber freely before you seat a bullet to find the lands. Might need to anneal your brass as well. If it's work hardened, you might be getting too much spring back when sizing and not actually setting the headspace correctly

Might also be that your extraction cam on the bolt handle is not timed correctly.

 

[Just Dave]

That's what I thought,. So I found some other brass and ran it thru FL sizer, still resistance.. So out of desperation, I take my Hornady modified case, and even it still "drags" on close. The part about it not "clicking" and the effort to pull bolt back made me think it was the rifle,. But I grabbed another 700 in different caliber, and got similar results.. First gun was a factory chambered 223. Second gun is a trued 700 action on a Douglas barrel..

 

[Ledd Slinger]

That's what I thought,. So I found some other brass and ran it thru FL sizer, still resistance.. So out of desperation, I take my Hornady modified case, and even it still "drags" on close. The part about it not "clicking" and the effort to pull bolt back made me think it was the rifle,. But I grabbed another 700 in different caliber, and got similar results.. First gun was a factory chambered 223. Second gun is a trued 700 action on a Douglas barrel..

So we are talking about bare brass without a bullet now correct?
I would anneal the brass and re-size and try again. Set your FL die to knock the shoulder back an extra .004"-.006" As you knock the shoulder back further, you will also be sizing the body base a little more. With annealed brass and headspacing increased, there shouldn't be any issues.

Are you also loading the brass in the bolt face prior to chambering and closing?

 

[Just Dave]

So we are talking about bare brass without a bullet now correct?
I would anneal the brass and re-size and try again. Set your FL die to knock the shoulder back an extra .004"-.006" As you knock the shoulder back further, you will also be sizing the body base a little more. With annealed brass and headspacing increased, there shouldn't be any issues.

Are you also loading the brass in the bolt face prior to chambering and closing?

Yea, The first cases were virgin Lapua, so I grabbed some Nosler and Hornady cases and set die tight.. I don't have a SB die for my -06, but I do for my 223.. Maybe I'll go back to the first gun, and resolve the issue with bolt not dropping on that one..