Speer reloading data question

[layusn1]

I noticed that the Speer reloading manual changes the order of the powders they list according to the bullet weight. For example, for their 90gr bullets they list 34 to 38 grains of Varget in the first block and for the 100gr they list 38 to 42 grains of H450 (with CCI small rifle magnum primers). Is this their way of indicating the powder they determined to be the most accurate with that weight bullet? If so, how do you read their data...they are in a spreadsheet type setup so is the powder right under it the next best powder or is the one to the right of it the next best powder?

Also, I noticed in the very last block, bottom right, of some of the bullet weights they list reduced loads. They have, for example, IMR4198 with 17 to 19 grains of powder for an 85gr bullet. What is this load used for? All of the other data they list for that bullet are in the 40 grain range.

I'm guessing this information is in their manual but I bought one of those single caliber load books so I don't have access to that info. These are values for 243 Win, just in case anyone was wondering. Thanks.

 

[Walkalong]

The Speer #13 lists them by velocity. Slowest to fastest. Of course, they do not give pressures etc. They supposedly stop where pressures are close to or at the top with good accuracy. They will quit with a powder below max if the pressure starts peaking quickly at that point with a certain powder.

I wish they would include pressures, but I think they worry we will see where they stopped a bit short of max and then think we can go higher with the charge weight. Just guessing of course.

The 4198 reduced load is just that, a reduced load. Perhaps for practice or for the recoil sensitive. In the #11 manual they gave a lot of reduced loads with SR4759 with bigger cases. #11 also listed that 4198 reduced load for the 90 gr. bullet in it as well.

17 grs 4198 for 1766 FPS
18 grs 4198 for 1873 FPS
19 grs 4198 for 1990 FPS

22" barrel Ruger Mod 77 WW cases and CCI-200 primers

 

[Shoney]

Pressure, whether derived from testing PSI, CUP, LUP and/or physical signs of the pressure on the brass, is how the manuals determine their minimum and maximum loads. All load manuals have data well under the SAAMI pressure specs (lawyer driven data). Combinations of factors can cause great variances in pressure. Here are a few factors:

Primer: strength, brisance - is a measure of the rapidity with which an explosive develops its maximum pressure
Barrel: length; tightness of chamber; tightness of bore; height of the lands; distance of bullet to lands; temperature of barrel;
Bullet: diameter; bearing surface of bullet, alloy of bullet; shape of bullet; crimp; seating depth/OAL (affects cartridge volume);
Brass: new/used; elasticity; manufacturer, wall thickness; volume;
Powder: new, aged, old, batch powder was from;
Weather: ambient air temp., barometric pressure, humidity; elevation above sea level
Other: I am sure I have not listed all

Now, mix and match them. Anyone care to calculate the number of possible combinations?

My point here is that published pressure data should be used as a guide, not as absolute gospel, because your weapon and load will be different. Looking for pressure signs in rifle bottleneck cartridges is a good (not foolproof) indicator of safe loads. There are no reliably safe pressure signs for straight wall pistol cartridges.

Your goal should be to develop the most accurate load, not fastest or closest to max listed load. Some of my accuracy loads are well above max, with no pressure signs, while most are middle to upper load range.

Good shooting!

 

[Mal H]

The Speer #13 lists them by velocity. Slowest to fastest.

One slight correction, Walkalong. Speer list the loads from fastest to slowest for the max determined load of a particular powder.

layusn1 - Speer doesn't list what they consider to be the "best" powder for a particular bullet. Nosler does do that as does Hornady. To be honest, I'm not sure it is all that helpful to us. What they achieved in the way of accuracy with a particular powder/bullet/case/primer combination on the day they tested the loads in their firearm could, and probably is, completely different from the results of the reloader using their manuals.

 

[layusn1]

hmmm...to quote what the Speer section says...We found that 4350, Reloader 19, and similar propellents worked best with most bullet weights.

I think I want to go with the 100gr for better powder economy and less velocity...hopefully less barrel wear. I really like my Browning A-bolt and want to keep her going as long as possible. I like ball powders with the CCI small rifle magnum primers...seemed to be the most accurate for my 223 loads but I have a lb of Varget I might try since I need to use it up on something.

I hear rumors that people can do their own trigger weight adjustments on these rifles. Anyone know if that is true and how to do it or should I take it to a smith? Thanks.

 

[Walkalong]

Quote:
The Speer #13 lists them by velocity. Slowest to fastest.

One slight correction, Walkalong. Speer list the loads from fastest to slowest for the max determined load of a particular powder.

I kinda sorta said that, but you stated it more clearly.

 

[Shoney]

layusn1: I hear rumors that people can do their own trigger weight adjustments on these rifles.

The proper way to adjust the Browning A-bolt trigger is to replace the spring with a lighter spring, or replace the entire trigger assembly with an adjustable aftermarket trigger.

If you are so inclined, you can remove the spring, clip off a 1/4 turn at a time, reinstall and test. Repeat until the desired weight is achieved.

 

[layusn1]

Is it hard to change the spring if you have never done it? Would it be better to let a smith do it?

 

[Shoney]

It is a relatively simple proceedure. If you have the owners manual for the rifle, there should be a section that explains it. If not you might try the browning site for the info on line. Otherwise, contact Browning for a manual or see a smitn.