Odd 30-30 Chronograph Results on 311041GV _ Any Ideas?

[Foto Joe]

After putting many hundreds of rounds through my Henry H009B 30-30 using different loads, OAL's etc. I finally decided that I probably had my pet load set up for hunting so I broke out the chronograph yesterday. To say the least, the data was interesting and at least to me confusing. The load is 20.0 gr of IMR 4198 under a Lyman 311041GV using COWW +2% tin and air cooled. Nominal boolit weight is 173.5 +/- .5 grains.

The configuration seems to be the most accurate for me and prints about 4" at 100 yards using a Weaver 2.5 power scope from a makeshift rest. Hardly match grade shooting but for knocking down a muley it's acceptable for me, keep in mind I'm a pistol shooter and am pretty ignorant of rifles and what they eat.

Here's where things got interesting, the first shot with that load passed the chronograph at 1,817 fps and when I saw the readout I was pleased that it was moving down range at such a good clip (by the way I fired 3 fouling shots before the first one over the chronograph). The next four shots were 1,680-1,688-1,685-1,694. I let the barrel cool off for a few minutes while I looked at where I was hitting the target then loaded the second five rounds and the results were 1,813-1,690-1,687-1,710-1,715. It appears that the first shot with a cold/cool barrel sends the boolit down range at a considerably higher velocity that subsequent shots and I'd like to know why. Each load was hand weighed and spot on for powder charge and although the boolits weren't "exactly" the same weight they were +/-.5gr and I wouldn't expect that small difference to result in such a deviation in velocity. I'll add that I also chronographed 21.0 & 22.0 grains of 4198 as well and the results although faster indicated the same cold/cool barrel difference in velocity. I also ran a half dozen 300 Win Mag rounds over the chronograph for my brother (jacketed) and those were all single digit differences in velocity.

Even though the rounds are hitting in "my" acceptable range for accuracy I'm confused as to why the strange chronograph results. I realize that a lever gun "Is Not" a bolt action rifle and I love this gun and am not about to abandon it. Is it me or is this just part of the art and mystery of shooting cast boolits out of a rifle?

[Bzcraig]

I'll be watching for responses on this one

[HeavyMetal]

How are you loading the gun?

It could be the first round is being fed by hand the rest from the tube mag. or are you loading each round one at a time?

I was amazed when I saw the difference this made in an old 94 until the mag tube got fitted better.

Play around with "feeding" styles and see what your chrony says.

[Yodogsandman]

Your powder could be position sensitive. Try raising the barrel before each shot. If the numbers improve, a small tuft of Dacron over your powder charge should correct it.

[243winxb]

This

Your powder could be position sensitive.

I feel IMR 4895- 27.5 gr- 173 gr gas checked or H4895 is a better choice of powder for the 30 WCF (30-30). Same bullet i loaded.

[williamwaco]

1680 to 1820 is an extreme spread of 140 fps. That is not unusual at all. A filler might reduce the spread. (Or might not.)

[Tatume]

These data represent a fairly small sample. However, I've seen revolver ammunition (especially the large cased 454 Casull) shoot lower speeds for subsequent shots after the first. The first shot appears to pack the powder against the base of the bullet. Thin tufts of Dacron will not cure this, as recoil momentum just packs the Dacron too. As suggested, try single loading your ammo. If you get more uniform spreads, this may be your problem. The only cure I've found is to load a larger volume of powder, which usually means a change of powder type. H4895 (also IMR4895) is one of the most versatile powders available, and may be your best choice.

[leadman]

I have seen boolit lube cause this also. How much time between groups?
I do agree a change of powder may reduce your group and speed up your boolit. I use H4895 and the Lyman 311041 in my 21" tapered Contender barrel. Velocity is over 2K fps and accuracy hold around 1 1/2" at 100 yards.
I use Carnuba Red boolit lube for these loads.

[Larry Gibson]

If you are not using a filler with that load then powder positioning is the cause for the high extreme spread, especially for just 5 shots. If you are loading the magazine with the 5 shots then the powder is position differently for the first shot because there was no recoil and the 1st shot was probably levered in differently. If you dropped one in the chamber and then loaded 4 in the mag the one in the chamber definitely has the powder positioned differently.

If you've any still loaded run the test again but raise the muzzle before firing each shot to settle the powder at the rear of the case. If you've none loaded then drop to 19 gr and use a 1/2 gr Dacron filler.

Larry Gibson

[Foto Joe]

Well, well, well...this is exactly why I posed the question and the answers have given me a totally different direction to look. I was making the assumption that the cold/cool barrel was the culprit and never took into account that recoil might be affecting the powder. The way I was loading was to load 5 in the magazine and lever the first one in. I think what I'll do is to simply load one at a time at the next go 'round and see if I can prove the theory given above. Also I wanted to ad that I'm using Lyman Super Moly for lube.

[Larry Gibson]

Joe

It's probably, what, 80 - 90 degrees up there......just plain freezing if you ask me........you should come back down here where the weather is fine......I've got 'em on ice

Larry Gibson

[243winxb]

I'm using Lyman Super Moly for lube.

Might be a lube problem? Try plain old 50/50 lube, that works at a lower temperature. http://www.lsstuff.com/lube/ Melt Temperatures-

Lube working temp melt temp

50/50 room temp 162F

BAC room temp 162F

2500 room temp 162F

Carnauba Red 100F 162F

Commercial 160 105-130F 165F

Commercial 190 130-155F 190F

[Foto Joe]

I've had good luck so far with the Super Moly and supposedly is a good lube for rifle loads such as the 30-30. I switched over to it from Lyman Alox simply because I had collected two sticks from somewhere. It is slightly less messy than an NRA 50/50 lube.

As far as the temperature is concerned Larry I'm afraid that you didn't take into account that our summer ended a couple of weeks ago when the leaves started changing. We had snow in the mountains last weekend and the WX man is calling for 50% chance of snow down low here on Wednesday (5,000 ft).

[leadman]

Many lubes work well to prevent leading but have a tendency to throw the first shot out of the group. I have had this happen with LBT Blue Soft and a couple others.
Larry could be right on the powder position. It will take some experimenting with one change at a time to nail it down.

[Foto Joe]

I fully agree with a clean barrel not necessarily putting the boolit where you thought it was gonna go. I did fire three "fouling shots" prior to starting this little experiment so I'm hesitant to blame the lube simply because the oddball's were always the first fired from a loaded magazine. I of course blamed barrel temperature but I'm such a simple man and when I should over think things I don't. Never ask me to build an outhouse or my wife will tell you a story.

[Larry Gibson]

"Snow"........what's that, I forget?

While I don't "do" anything with molly in it anymore it's not the lube unless it actually was close to freezing when you ran those tests. From many, many cast bullet loads fired over the years in lever action 30-30s with cast bullets and including 4198 powder......it is the powder positioning that is the culprit. Drop to 19 gr, use the 1/2 gr Dacron filler......all will be well.

Larry Gibson

[Foto Joe]

I'm curious as to why if my 20.0gr loads seemed to print best you'd recommend that I drop to 19.0 gr? And exactly where do I get my hands on Dacron filler?? My wife will probably notice if I take one of the pillows off the couch.

[frnkeore]

I fail to see how it can be the powder position if, they were all levered into the chamber and ONLY the first shot had the single high velocity. The ES was exceptable on all other shots, indicating that it isn't position sensitive.

Frank

[rintinglen]

If you can stand the estrogen overload, Joanne's and Michael's sell polyester pillow fill--same basic stuff as Dacron. I am currently using bamboo fiber sold for the same purpose, (but it's ORGANIC--says so on the label.) The reason for dropping the powder charge is that adding a filler will raise the pressure of the cartridge when it is fired.

[TXGunNut]

My velocity readings tend to climb with temp so I'm thinking positional sensitivity as well. I don't like fillers so I use powders that aren't position-sensitive or powders that fill 90% or more of the available space...no easy task with today's powder situation.