Wobbly and Idescribe, or anyone with Experience with Alliant Red Dot, Look Here

[Smitty79]

So the Alliant web site has the following load:

45 Auto    230 gr Speer LRN    Speer    1.27    5    CCI 300    Red Dot    5.1    841    -

My loader was set for 1.2, and I know that OAL runs in my Dan Wesson 1911.   So I loaded a ladder from 4.4gn to 4.8gn with my 230gn blue bullet RN.

Lyman manual says 4.5gn, 1.27 OAL gives 750.

I get to the range and get 850 fps.  Their load data doesn't specify a barrel length.   I don't see barrel length in the Lee manual either.   I would be surprised if they used something shorter than the low 4s.

Am I doing something wrong?  All I want is 770 from the DW.  That's enough to make major in all of my 45's.

[jameslovesjammie]

You're comparing three different bullets with three different types of lubrication on them...there are going to be velocity differences. 

LRN from one brand is not always the same as LRN from another brand.  There are often dimensional differences between them.  Add that to the fact that the Speer bullet is swaged bullet with a light graphite-type tumble lube, the Blue Bullet has their polymer coating, and the Lyman is conventionally lubricated with Lyman's own lube, and you're not going to get exact published velocities.

[Wobbly]

Exactly. The load manual is just going to get you close enough so that no one gets hurt. It's up to you to tweak that load until it does what you want. Good thing you have a chrono.

Ideas...

? Obviously, at your preferred shorter OAL, you can lower the load even more.

? Lowering the load may call for re-springing the gun to retain good function.

? Red Dot burns good, but does not meter really great. Therefore you might not want to trim your load to the bare mathematical minimum.

[jwc007]

I regularly run 4.7 grains of Alliant Red Dot under a cast or plated 230 grain RN or FP, and it makes USPSA Major out of the slightly shorter 4.7 inch barrel of my .45 Witness.
Velocities out of my 5 inch Colt 1911 typically run 780 fps or better. 

Alliant Red Dot is typically my "go to" powder for the .45 ACP.

[Smitty79]

Still seems strange that I?m going to make major a half a grain lower than expected from manuals.  Usually I?m much closer.

I did see more of an ES than normal.

[IDescribe]

I have some Red Dot but have not once loaded it.

In addition to your being .07 shorter than the load data, as James pointed out, there can be other dimensional differences, and .070 shorter may be .100 deeper. That can account for a pretty big difference in velocity for the same powder charge in 9mm.  I can't say, though, for .45ACP.  Bigger case, lower pressure, probably not as dramatic a change per tenth of a grain. 

[M1A4ME]

A larger SD in velocity doesn't always = larger groups.  I've read several posts over the years where people mention the loads with the smallest SD did not yield the smallest groups.  They comment on it, wonder about it, and don't come to any hard conclusions.  That just happens, sometimes.

And, if you get noticeably smaller groups, why worry about SD?  Reload your ammo and shoot smaller groups.

[Wobbly]

Right. SD on Velocity simply tells you how tightly you're able to control OAL (bullet depth) and powder measurements. If you're using big flake powder (like Red Dot, Unique, or 700X) in a mechanical powder measure, then precise metering of powder isn't always physically possible. But then, variations of 6-10 individual flakes between cartridges doesn't always translate into bullets going haywire.

 

[IDescribe]

A larger SD in velocity doesn't always = larger groups.  I've read several posts over the years where people mention the loads with the smallest SD did not yield the smallest groups.  They comment on it, wonder about it, and don't come to any hard conclusions.  That just happens, sometimes..

This a suspicion - - no evidence or testing, but I suspect "accuracy nodes" can explain why narrow SD doesn't necessarily mean smaller groups.  If a particular bullet in a particular barrel hits peak precision between 750 and 790 feet/sec, and the load that averages 770 for whatever reason has poor SD, that load is still going to produce tighter groups than a load with an average of 820 feet/sec with excellent SD.

[Wobbly]

This a suspicion - - no evidence or testing, but I suspect "accuracy nodes"....

Well sir... Of all the personages on this forum, I'd suspect you'd be the one to "node" that.

 

[Smitty79]

I went back to the range this morning.   I'm running 4.0 gns and average 180.5pf.   I've never seen this much of a percent difference in charge weight between what I expected for target power factor and what the I expected based on published load data.

Some of it may be that my Chrono reads a little fast.  My 9mm ammo chrono'd 884 fps at the section match last week.  My chrono averages more like 910.   Could have been temp sensitivity for HP38.   Chrono day was 94.   I tested the load at 55.

[Wobbly]

I thought there was a thread on Red Dot powder, but I can't find it.

I'll dig up some reports.