Mandrel Musings

[Rocketmandb]

Per @Newbie2020 request, I was able to add in 10 rounds that I used a mandrel on, but no lube. I added the data to the seating force post above. As per data from the range, below I've added the velocity next to the seating force - I don't see much correlation there.

The temperature was more palatable at 70 degrees, and the velocities got back down to where they should be (mid 2900s). Note that overall, the ES/SDs were down today vs. the last.

Seating Force (lb) and velocity (fps), No graphite lube, no mandrel
68 - 2941 fps
60 - 2948
90 - 2949
55 - 2945
86 - 2962
58 - 2965
53 - 2936
63 - 2942
72 - 2957
37 - 2958
ES: 53 lb / 29 fps
SD: 15.65 lb / 9.2 fps

Seating Force (lb) and velocity (fps): Graphite lube, no mandrel
47 - 2940 fps
40 - 2936
38 - 2944
52 - 2951
48 - 2945
27 - 2955
58 - 2943
48 - Did not register
51 - 2946
45 - 2957
ES: 31 lb / 21 fps
SD: 8.2 lb / 6.43

Seating Force (lb) and velocity (fps): No Graphite lube, mandrel
25 - 2966 fps
28 - 2949
29 - 2957
19 - 2953
29 - 2945
23 - 2964
25 - 2963
27 - 2963
24 - 2967
26 - 2952
ES: 10 lb / 22 fps
SD: 2.91 lb / 7.37 fps


Seating Force (lb) and velocity (fps): Graphite lube, mandrel
21 - 2953 fps
21 - 2950
21 - 2956
23 - 2949
23 - 2951
22 - 2956
23 - 2959
22 - 2955
22 - 2944
25 - 2955
ES: 4 lb / 12 fps
SD: 1.19 lb / 4.14 fps

 

[Rocketmandb]

I didn't have time to draw up my conclusions when I posted the data last night, so I'll take a quick stab here, as well as talk about what's next.

- As mentioned, all the ES/SDs were back down to where I expect them, with the standard coming in even lower than normal (I usually get mid to upper 4s with this rifle). To compare, the standard process SD came in at 5.9 fps on the hotter day 1, while these came in at 4.1 yesterday. The non-standard loads first came in at 8.7 fps on day 1 and the same configuration (lube, no mandrel) came in at 6.4 fps yesterday. This results in differences of 1.8 (31% drop) and 2.3 (26% drop) respectively. I mention this because this "lube, no mandrel" configuration basically matches up with the previous day on a % basis when adjusted for temperature changes.

- Interestingly, the "lube, no mandrel" and "mandrel, no lube" performed very similarly at the range, despite the "mandrel, no lube" being markedly more consistent in seating force. I'm guessing that the "mandrel, no lube" results at the range were abnormally high, but I need to test this again to validate. Thanks, @Newbie2020 ... This will have to wait, as I'm getting some stock work done on my 6mm, so it will be out for a while.

- The "no mandrel, no lube" is clearly the worst of the bunch, and based on previous testing, along with the dramatically worse seating force consistency, this should be no surprise.

Next up I'm going to be testing the results using different bushing sizes on my 300. I just got my new custom sizing die in, so I can start loading for the 300 again. As mentioned previously, I see much higher variability on seating force on my 300 than my 6 - I use a relatively smaller bushing on the 300 than the 6. Is the seating force inconsistency simply due the larger round, or is it because of the bushing size? That's what's next.

 

[Halfnutz]

Thanks for taking the time to share this with us.
It coincides with my ordering all the stuff required to hopefully pull this off.
Ordered an Anneleez with the expectation of a 4-6 week delivery date, if it shows today like the tracking says it will have been 6 days.
21st Centry 6.5 tin coated mandrel and die, no tracking yet.
Wilson Seater and K&M arbor w/ indicator should be here in the next day or two.
About $800 to get single SD and ES hopefully the juice is worth the squeeze.

 

[Rocketmandb]

Thanks for taking the time to share this with us.
It coincides with my ordering all the stuff required to hopefully pull this off.
Ordered an Anneleez with the expectation of a 4-6 week delivery date, if it shows today like the tracking says it will have been 6 days.
21st Centry 6.5 tin coated mandrel and die, no tracking yet.
Wilson Seater and K&M arbor w/ indicator should be here in the next day or two.
About $800 to get single SD and ES hopefully the juice is worth the squeeze.

To make you feel a little better about spending some coin, I'd argue:

- Your Annealeez will get you more brass life on top of anything else
- Your 21st Century mandrel/die is about the cheapest piece of equipment you can get that will yield tangible results.
- I prefer the Wilson type seater and associated arbor press over standard seating dies just from an ease of use standpoint - AND - you can take the setup to the range for seating depth work.

 

[Halfnutz]

I did quite a bit of looking before deciding on those and our thoughts on the manufacturers concur.

 

[phlegethon]

When I’ve used graphite lube, it really doesn’t feel any differently. I wonder if I’m doing something wrong?

 

[Rocketmandb]

When I’ve used graphite lube, it really doesn’t feel any differently. I wonder if I’m doing something wrong?

Doubtful that you'd be able to feel the difference - the average seating force numbers I recorded and posted above are not much different between using lube and not. The average difference is only about 3lbs, though the consistency is better when using lube.

As I mentioned, I think the higher ES/SDs measured in the no lube group were contributed to by something other than just the absence of graphite. I won't know until I run another test.

EDIT: I could definitively tell the difference with the other two groups.

 

[iceng]

@Rocketmandb I'd like to thank you for sharing results and your data. I've recently started testing with mandrels and have noticed a marked improvement in seating, but do not have enough data to test at the range (I personally like having 100 rounds of data, that way no one can argue about a small sample size).

I'll attempt to take a photo tomorrow of my custom seating force indicator. I'm sure I could sell it, but have other cool things I make (plus I currently don't sponsor the hide).

Keep up your good work and the data coming. Its solid work.

 

[max1840]

This information is wonderful! Thanks for taking the time to do it and share it. Much appreciated.

 

[Cfshooter]

Thank you so much for sharing! I am always debating if lubing helps or not with FPS ES, SD, and group size on target.

 

[Rocketmandb]

More mandrel data, this time from neck turning with my 300 PRC cases.

What got me going on this data gathering exercise was the marked difference between the consistency of seating force on my 6 BRA vs. my 300 PRC. The process is identical on both and I wanted to figure out the reasons why.

The differences between the two cases are:

1) Neck size (obviously)
2) Brass type (6 BRA = Lapua, 300 PRC = ADG)

Otherwise, literally everything is the same (die manufacturers, process, etc.). Somewhere on this site I've mentioned before that I would cull out any case that fell outside of roughly 10-15 lbs of seating force. In a box of 50, this would usually mean 4-6 rounds that would be used as foulers, etc. So, again, why so "bad" on the 300 vs the amazing results I get with the BRA?

One of the things I considered a likely culprit was the consistency of neck thickness. I find Lapua brass to be one of the most, if not the most, consistent. I measured some differences (somewhat minor) in the ADG brass. A thicker neck will spring back a different amount than a thinner neck, meaning with inconsistent cases, after you mandrel, you're left with slightly different inside neck measurements. How much and will it matter?

To find out, I bought a 21st Century neck turning lathe for 300 PRC and went to town. I turned and measured seating forces on 25 turned cases vs. 25 unaltered cases. The results are below:

Turned cases:
# measured: 25
Average seating force: 40.5 lb
ES: 11 lb
SD: 2.63 lb

Non-turned cases:
# measured: 25
Average seating force: 44.7 lb
ES: 18 lb
SD: 4.37 lb

 

[newageroman]

nice continuation of data. thanks!
I've recently become bored and started neck turning (was previously annealing and mandrel sizing already). One other thing I've started doing is inner neck honing. It seems that annealing leave a reddish/orangeish oxide on the inside of the case. I wire brush this first, then take a smaller caliber brush and a 1.5" square piece of fine wet sandpaper (3000 grit) and hone the inside with a hand drill attached to the brush. The result is a near mirror finish on the inside of the necks. I don't have an arbor press but seating definitely feels much smoother. Also much props on the 4 degree K & M champher tool. It cuts very precisely and has a depth stop.

Now that I have the bulk of the work done (cases turned and fired) - I'm hoping my numbers drop a bit more.

 

[Feniks Technologies]

nice continuation of data. thanks!
I've recently become bored and started neck turning (was previously annealing and mandrel sizing already). One other thing I've started doing is inner neck honing. It seems that annealing leave a reddish/orangeish oxide on the inside of the case. I wire brush this first, then take a smaller caliber brush and a 1.5" square piece of fine wet sandpaper (3000 grit) and hone the inside with a hand drill attached to the brush. The result is a near mirror finish on the inside of the necks. I don't have an arbor press but seating definitely feels much smoother. Also much props on the 4 degree K & M champher tool. It cuts very precisely and has a depth stop.

Now that I have the bulk of the work done (cases turned and fired) - I'm hoping my numbers drop a bit more.

Just something to keep any eye on.

Anytime you start substantially reducing friction (polishing/honing and/or lube) you may need to increase the interference fit.

Otherwise you may experience bullets slipping forward or back when chambering or moving rifle around or under recoil.

 

[Clownbuster]

.

 

[Cfshooter]

.

Thanks for refreshing this, great post!

 

[Rocketmandb]

I should add that for my 300 PRC, I've switched to Lapua brass. I've found the consistency to be markedly better than ADG - very much on the order of where the turned cases were for ADG.

Now, most my attention has turned to my new 37XC. I'd love to add some of that data here, BUT I CAN'T! No way for me to get a seating die for the arbor press without getting one custom made @ $800. Also, the only brass I have is Peterson. It seems to be doing pretty well, but I can't test to know how well.

I'm actually considering dropping down to a 33XC on my next barrel because LE Wilson makes a seater for this AND there are these things called Berger 300s! I've decided I hate shooting solids at longer ranges.

 

[phlegethon]

Now, most my attention has turned to my new 37XC. I'd love to add some of that data here, BUT I CAN'T! No way for me to get a seating die for the arbor press without getting one custom made @ $800.

 

[Rocketmandb]

Looks like it only goes up to .338 and goes into a standard press - not for an arbor press.

 

[phlegethon]

Looks like it only goes up to .338 and goes into a standard press - not for an arbor press.

Oh I forgot the calibers. But you can always use a regular press…