Armory Sponsor
Posted: 9/10/2012 3:12:02 PM EDT
|
Got my new LNL AP set up and love this machine so far. This weekend I loaded a few hundred rounds of 9mm. I took careful measurements of the neck expansion, COL, final case mouth and was getting tolerances of + or - 0.002 at the most. Very impressed. Also, the LNL Powder Measure was sending 6.7 grains of Accurate #7 every single time.
Anyway, my question is this: I notice that (with empty shell plate) the ram seems to slightly bump to the right at the top of the stroke. This appears to be a result of the handle that is canted off to the right, so when applying pressure it can bump the linkage/ram slightly. I linked to a video that helps demonstrate. Is this normal and expected? Will this effect precision or accuracy? LNL AP Question - Youtube |
| I just went and looked at mine. With my 223 sizer die installed and the ram all the way up I get 0 movement. With the die removed and the ram all the way up I get 0 movement. The only time I get a slight wiggle (much less than yours) is with the ram approx 90% of the way up. |
|
That seems like a lot of wiggle in the linkage. Does the subplate rotate when you pull the handle down and to the right? How about down and left? Straight down?
Let me look at mine and see what might be causing that slight rotation in that last half inch of travel................. |
|
Mine has NO rotation at the top of the stroke.
A few things I observed to check: Your linkage is totally clear and not bumping against something Check your primer slide guide bar for lateral bends Your powder drop can make contact with the shellplate at the very top of the stroke, if yours does make sure it is not inducing the rotation. Ensure the pawls are not somehow making contact at the top of the stroke Inspect the ram cylinder and the bottom of the frame for any abnormality My guess is that the linkage movement has something to do with it as that portion of the stroke is nearing cam over. |
|
Look just under subplate at the ram. There's two countersunk, tapered machine screws. These need be tight and centered inside countersink on each side of ram. The canting described is result of either machine screws not centered and loose or subplate has been set to high. I'm questioning, but not disputing oal variance of .002. Usually fellas will see around or over 0.10 variance if subplate has noticeable play. If there was, say a 0.010 tilt to one side you would have variances to half or all of the distance of tilt.
Hornady used to shim between plate and ram to secure sub-plate from tilting. Recent owners have said Hornady will no longer provide the needed 0.005 or 0.010 shim. I understand why. Set screws could hypothetically deepen both countersinks over time, wearing countersinks upwards. Leaving press worse than before. Mine's been shimmed and set screws set with Locktite. Not worried about screws coming loose, but then I pay attention while doing a pre-run inspection before runs. There's an OP on this in gateway threads, my block. Page 2. Doug is my contact at Hornady for all things technical. Doug is a shooter and hand loader. P.S, FYI. All progressives have an issue both top and bottom with horizontal play. Some worse than others. The two worst presses to tune, minimize play are Lee Pro1000 and Dillon XL650. Most folks ignore variation of 0.010 oal. |
|
UPDATE: Well, I called Hornady about my question and they quickly put me in touch with a very polite Service Technician who explained thoroughly. He also offered to inspect and replace anything if I would like to send in the press. Basically, the bump is caused because the ram stops when the flats from the “toggle” meet the flats from “yoke”. My left flats meet while there is about a 1/32 gap on my right flats – see illustration. He assured me that this would not be an issue for the reason below.
https://lh4.googleusercontent.com/-exjh8dw7Qiw/UFEPAIdCVFI/AAAAAAAAAGs/ZlUz-kfgUBg/s640/gap1.jpg He said that the LNL AP press is engineered with “wave washers” to provide limited flex on the downstroke (I mean ram up) so that the shells can self-align into the dies. Any movement at the top is irrelevant because at that point all the shells are already fully inside the dies and concentricity/COL/expansion/powder will not be affected by ram movement if present. The die itself will determine the precision at that point. There would only be a concern if there was flex on the upstroke (ram down - of which I find none) because it may misalign a primer. https://lh4.googleusercontent.com/-N97ry84gV-E/UFEUgmoEZJI/AAAAAAAAAGw/7FCOHWhJm-U/s640/wavewasher1.jpg Even though it won’t make a difference in production, I will slightly file down the left flat so they meet at the same time, just an OCD thing, probably. Like I mentioned at the top, it seems to be working extremely well so far and is obviously a favorite of the experienced pros in this forum. 1911Smith - thanks for your input as well. Your diagnosis was correct that this is unrelated to the subplate tension. Also, I should have clarified that by + or - 0.002 I meant over or under which is a 0.005 variance, much more in line with your expectation there. I actually got that standard as an acceptable tolerance from your advice on an earlier post concerning COL where you used 0.003 as your goal and 0.005 as acceptable. I really try to learn from you guys here! |
Welcome new team member. Lots of new features for you to play with. Check out the Team forum (you were locked out before) and look around. Up in your profile (icon at the top of the page next to your log in name)is where you can add an avatar and choose your title and sig line.
|
|
Quoted:
Thanks! Just finished filing that down, took like 15 minutes - now there is no rotation as displayed in the original post. Oh, and I joined the member team. 
And now I'm off to look at my press to see how mine looks although I've never noticed the condition you found on yours. |
Armory Sponsor