303 British Load data for 150gr speer sp flat base !

[armenjs]

What would be the starting grain for loading 303 with Speer 150gr sp. powder to use is imr4895.
http://data.hodgdon.com/cartridge_load.asp the link doesn't show a test data. for IMR4895.

[mdrim13]

I dont know about speer or imr4895 but I have had good luck with Hornady 150 gr flat base soft points and reloader 15 powder. If you dont get the results you are hoping for, yu might try it out.

mdrim13

[jmoore]

They have a maximum load, but no starting load... Generally that means reduced loads were unsatisfactory. Probably pressure swings are too great as the powder burn is not uniform at the lower pressures/loading densities. I'd try another powder in this case!

[armenjs]

I looked at the Speer Manuel and they seem to like imr4895 with 40grain 150sp flat base. Lyman on the other hand doesn't show the test data for imr4895 instead they have H4895 starting is 37gr. H4895 is a higher burning rate than the imr4895. I always reduce the starting load data by 5% and move up to find the sweet spot. For safety concerns/ something happens I am always go 5% lower the suggested starting load.

[smle303br]

My Speer Manual #10 shows Speer 150 Gr. SP using IMR 4895 as follows: 41gr-MV 2663; 43gr-MV 2779 and max load 45gr-MV 2907. I have used this load at 43gr. it is OK but prefer to use Hornady Bullets with 0.312" dia.

[armenjs]

Just got back today. used Speer 150gr sp/ imr4895 40grpowder result were ok at 100Y
total 19 shot all in 4 inch spread. Only onequestion. I am getting powder residue from nick up! More than normal. Iam not crimping the cases. only using one shot at time bench shots, loading one at a time.

[Parashooter]

You're seeing soot on the necks because the bullet base is leaving the case before the neck has expanded to seal against the chamber. This is to be expected with a short bullet and a ~34000 psi load, which is what you're shooting.

If the soot bothers you, there are several approaches that may eliminate or reduce it -

• Heavier/longer bullets
• More powder
• Faster powder
• Seat bullets deeper
• Anneal necks
• Size necks only to depth bullet is seated

For example, if you are happy with the velocity your load is giving (~2500 fps) you could get the same speed using ~33 grains of RL7 - but at ~43000 psi peak pressure, probably applied quickly enough to expand the neck before the bullet exits the mouth.



Many handloaders seem unaware that the case's shoulder area is normally thinner/weaker than the neck and therefore expands sooner. This is a natural consequence of how bottleneck cases are formed.

[rayg]

Interesting hydraulic effect on the thinner necks, Ray

[Parashooter]

Interesting hydraulic effect on the thinner necks, Ray

Looks like some further explanation is needed. In fact, the brass is normally thicker at the neck than at the shoulder and the forepart of the body. This is because the case is drawn as a cylinder with gradually tapered walls. When the final forming is applied, the reduced diameter of the neck results in the brass there becoming thicker than before neckdown, while the area just aft of the neck remains nearer the original thickness.

[armenjs]

Parashooter



You're seeing soot on the necks because the bullet base is leaving the case before the neck has expanded to seal against the chamber. This is to be expected with a short bullet and a ~34000 psi load, which is what you're shooting.

If the soot bothers you, there are several approaches that may eliminate or reduce it -

Heavier/longer bullets
More powder
Faster powder
Seat bullets deeper
Anneal necks
Size necks only to depth bullet is seated

Thanks parashooter great feedback Wow! To maximize my POI, i seated close to the rifling, and with 150gr i will get some soot like you said. i don't mind its good. check out my thread on the Enfiled side of this forum.