Rifle to rifle differences in load data a cause for caution.

[firebird74521]

It appears that some people get into handloading without taking any time to learn at least a little of the physics at work when the primer ignites the powder charge and how every little change in components can affect the pressure spike to dangerous levels. Some are just stufing powder into cases without any knowledge of how it works at all. Sub calibers have tiny cases and pressure builds fast because there is no large powder charge to burn through and little room in the case for the pressure to expand into. Just one almost instant burn and pressure spike. The tiny bore doesn't allow that pressure to expand much as the tiny bullet moves down the miniscule bore as does a larger caliber. The desire for extreme velocity in hand loading sub calibers without a constant watch for even the slighest pressure sign is a disaster waiting happen. Velocity is fun but a gain of 200FPS really does damn little for hunting varmints or anything else. The difference in gained PBR is little. It is more for bragging than anything usefull. Definelty not worth blowing half your face off.

[sicero]

Very good post Firebird 74521. Your experience shows thru.

When I bought my first SC rifle a few years ago I ordered a bunch of stuff from Kindler including a little magazine called Sensational 17s or something like that. I promptly sent it back as totaly worthless without pressure testing data. Kenny

[wally bennett]

Originally Posted by montdoug

I got my new Small Caliber News yesterday, good issue. Lot's of small caliber stuff. (Great article Alex).
In reading some of the articles as well as letters to the editor I was again struck by the same thing I find on the internet, rifle to rifle load data varies hugely and caution is always in order no matter what the source.
Two examples were, one the letter where an individual was getting 3,848fps with a 30 grain bullet in a .17 MachIV when in my MachIV 3,850ish is all of it with a 25 grainer.
The other was in Todds data on the VarTarg with a 32 grain bullet using N120. His top load was 19 grains and while I've only used N120 a little in my VarTarg I've used it enough to know 19 grains of the lot I have would be "way" over the top with a 32grainer in my rifle.
Lot to lot powder varience can't be overstated it would appear as are rifle to rifle variances.
As a long time reloader of bigger stuff it is obvious to me the smaller cases and smaller bores must be a lot more critical to such changes than I was used to in .223 and up stuff.
I can't get the image of Mntngoats rifle or Randy Mertas eye out of my mind.
The max load of my lot of H4198 in my Tact.20 for example using a 33 grainer is near three grains lighter than what I've seen published in a small caliber load book.

The stuff I read today just reinforced how different those writers experiences with their rifles and powder lots were from my own.
I guess we can't be too careful huh?

Hi Montdoug was thinking about a thread myself same topic i have been loading for about 30 years now for two 222,s a 243 and my own hornet and two other hornets in all the guns i always started low and worked up to the lowest max load in all the load data books then carfully increased to the max load of the others and in all cases i had no pressure signs at all and i used a mike on all cases before and after fireing and did not find any increase in head size or any bolt stickyness. THEN THINGS CHANGED!. I bought a 17A/H Barrel from Pac-Nor stainless match grade 24" long as well as the Sensational Seventeens book from Tod Kindler.( Dont get me wrong its a perfect barrel and after about 1,000 rounds i have failed to find any sign of copper even after trying all the copper removers i can get my hands on ) but the chamber size is so tight when i used the published load for fireforming i got a stuck case and it worried me.
It was 11.9grns of N120 behind a 20grn V/MAX The load i settled on is 10.5grns of N120 pushing a 20grn V/MAX at 3,528ft/sec my main load is 10.8grns of N120 pushing 20grn V/MAX for 3,640ft/sec CCI400 primers in both and R&P Cases.Published data is 11.6grains of N120 for 3.621ft/sec whilst i get 3,640ft/sec from 10.8grains published max is 12.2 grains N120 for 3,847ft/sec my gun puts out 4,080ft/sec for 12grains of N120 and a very sticky bolt I ONLY TRIED ONE!
SO YOU ALL BE CAREFULL OUT THERE YOU ARE NOT JAMES BOND YOU ONLY LIVE ONCE.Wally
Life is a bitch then you die (just make sure its not an overload that does it)

[wally bennett]

So thanks lads or lassies for pointing out the differences in different powder lots i honestly thought that powder manufacters would ensure the powders gave the same performance between lots ( i must be a bigger fool than i thought ) so i suppose its a good job that i have always loaded well below max loads so i will have to test my next lot (just bought ) of N120 against the remaining loads loaded with the last lot in my Pac-Nor barreled 17 Aclkey Hornet
I have had so much help reading the threads on the Saubier web site i have had to think again about many things i thought i new but somone else had better ideas.
Thanks Wally

[montdoug]

Howdy Wally and welcome.
When I first posted this thread Dan C. and I were both working on loads in our .20 Killer Bees. Both using the same Pac-Nor barrel I believe and both cut by the same reamer and same gunsmith. Same bullets and both using AA1680 but both were of course different lots. It amazed me how we both ended up at about the same velocities but with a significant difference in powder charge. What caused the variations . When I started looking at all the things that could be contributing factors it became real clear to me. Load data ain't like cookie recipes!!!
Without going into it at great length your .17 Ackley data is another good example. I use N120 and 20 grain V-Max's with WSR primers in WW cases and my charges and velocities are way different than yours.
It's a fascinating hobby huh?
Once again, welcome to Saubier.com .

[wally bennett]

Originally Posted by wally bennett

So thanks lads or lassies for pointing out the differences in different powder lots i honestly thought that powder manufacters would ensure the powders gave the same performance between lots ( i must be a bigger fool than i thought ) so i suppose its a good job that i have always loaded well below max loads so i will have to test my next lot (just bought ) of N120 against the remaining loads loaded with the last lot in my Pac-Nor barreled 17 Aclkey Hornet
I have had so much help reading the threads on the Saubier web site i have had to think again about many things i thought i new but somone else had better ideas.
Thanks Wally

Done a few test loads with my new lot of Vit n 120

Ruger 77/22H re-barreld with Pac-Nor stainless in 17A/H R&P Cases CCI400
Vit n 120 20grn V/Max oal1.810" (touch)

Old lot
10.8gr gave me 3,637ft sec 11.2gr gave me sticky bolt but i did not crony it

New lot
Up to 12gr now with no pressure signs ( crono broke a friend put a 22H bullet through it )but not quite the speed of 10.8gr of the old lot its a little low at 160yds so will try 12.2gr ASAP

Main thing is no pressure signs with i.2gr more powder and all other componants the same
Wally

[Remmynut]

As some know, I have sat here researching 22 hornet loads, tongue in cheek, just getting an overview of "RANGES" of charges some use and the powders, problems, Chony results..groups........etc.

Loading data and books vary as badly if not worse.

A few times Ive found a post by a gentleman using a Hornet and LGun.

"I've found that using the case for my "measure" and just filling it to the top and striking it off with a credit card is all I need to do for excellent groups and velocities" (not quoted but the same as")

I might "pass" on that one.

Might work........might not too.......scares me and Im fearless.

God Bless

[Daryl]

Remmynut - have you filed a case and struck it off to find what that weighs? Depending on brass make & if it's merely scooped - ie: in WW brass, it might be a load listed by Hodgdon - that is, it might be only 13.0gr. You did say the fellow used the case as a measure.

Merely look at Hodgdon's data - they sell the powder - they tested the powder and they should know what the powder does.
They used WW brass, WSR primer, 24" bl.
Their data:
30gr. bullet-13.0gr.
35gr. bullet-13.0gr.
40gr. bullet-13.0gr.
45gr. bullet-13.0gr.
50gr. bullet-13.0gr.
53gr. Barnes XFB-12.0gr. Very hard bullet - pressure listed as 39,000cup
55gr. bullet-13.0gr.

Looks like they felt the case capacity load is around 13.0gr. If you've loaded some, you've seen that dropping out of a measure into the case leaves very little room for the bullet in WW cases.

Their 13.0gr. load developed 28,400cup with a 40gr. and 24,000cup with the 35gr. I've tested up to a full case in both WW and RP brass and had NO adverse pressure signs in a CZ rifle. I've never lost a case in that rifle due to expanded primer pocket - in over 17,000 rounds fired now with loads in excess of the ones listed by Hodgdon - using Lil'Gun - up to 13.5g.r in WW cases and 14.4gr. in RP cases. The RP brass holds almost exactly 1gr. more than WW brass.

I think some people who are fearless should gain more information before becoming too firghtened.

[MarinePMI]

Originally Posted by Remmynut

As some know, I have sat here researching 22 hornet loads, tongue in cheek, just getting an overview of "RANGES" of charges some use and the powders, problems, Chony results..groups........etc.

Loading data and books vary as badly if not worse.

A few times Ive found a post by a gentleman using a Hornet and LGun.

"I've found that using the case for my "measure" and just filling it to the top and striking it off with a credit card is all I need to do for excellent groups and velocities" (not quoted but the same as")

I might "pass" on that one.

Might work........might not too.......scares me and Im fearless.

God Bless

I've shot PDs with a guy that does this. It works for him I suppose, but I can't just get my head around it (or cojones enough to do it myself). I like my eyes working...

[Remmynut]

As I said before it might WORK.....I have more issues with no mention of brass type, new or not, neck resized or full length or any mention of how many grains that was, estimated or not.

Might not BLOW but one has to wonder on consistancy in loads? Working and being consistant (half the reason I load) are two different issues but Ill admit, like the post above, it's tough for me to get my head around when we weigh each load down to .1 of a grain.

Dont think for a minute I wont try this and check the weights of the loads.

Ive never handled lil gun yet so maybe the powder size etc makes it pretty consistant doing that but I'll have to see in first hand is all. Its totally the other end of the spectrum from most loaders I know of.

Hey, if it works CONSISTANTY.......I may do it myself, but suggest it on the web as a recommendation? Nope.

No offense meant.

GodBless
Steve