MV depending on bullet type for same weight?

[reinwood]

Hi,

I am thinking of starting handloading and have a basic question (probably). I am in Europe and as bullet from US manafacturer are easy to get, it is not the same for the powders.

My question is the following, to which extend the MV depends on the bullet type: assuming I take the loaddata from a European manfucater (RWS, Lapua, etc.) for a 200gr bullet and I use a Barnes/Nosler Bullet of 200 gr instead? Will the MV be the same?

I am using mainly the 8x68s (a bit better performer than the 8 Rem) and except RWS, there are not much factory load available.

Thanx

 

[41mag]

Welcome to the forums. I hope that you find al your looking for here. There are a LOT of very knowledgeable folks who browse these pages.

I will try to help out with my experiences.

Generally speaking when I am working up loads for a specific caliber, I look for as much info on the particular weight bullet as I can find. This may or may not include the particular brand bullet I am wanting to use, as in your case. Things to pay particular attention to are the actual bullet composition. With typical cup based bullets, you can pretty easily duplicate or transfer to a degree the load data from one book to another for the same weights using the same powders. You simply need to drop down a couple grains in the load and work up.

However when switching to a solid material type bullet like the Barnes or some of the newer all copper types, you will need to start at the beginning loads in order to keep from experienceing higher pressures. The solid type bullets do not compress like the cup type bullets do. A similar case might be the Nosler Partition or similar makes. With the partition in the middle of the jacket, this might keep the jacket from compressing as it goes into the bore and raise your pressures up a tad.

As far as the actual velocities go, this will be dependent on more than just the load data. You rifle might have a tight or loose bore which might add or subtract from the actual listed velocities as well the powder lot might be a tad faster or slower than the actual test lot. Also depending on the type bullet and seating depth will also effect the pressures and velocity. It might get you in the ball park but you would need a chronograph to actually be somewhat certian. If your looking for the top end velocity from your rifle that I would suggest using a chrony to help out with the development as it will help you see the pressure spikes as you work up. If not looking for the top end it will also helpyou to quickly develope a drop chart for you load with out shooting up extra rounds doing the drop test at various ranges. You can simply apply the data to one of the programs and then test fire at range to verify and adjust for a final drop chart.

Well hope this helps, good luck on your loads. I am sure that if I missed something or didn't quite hit the nail on the head someone else should pop in with something soon.

 

[Boss Hoss]

One thing to be careful of when just assuming that the data developed from one bullet being transferred to another even if the total weight is the same is safe it may not be. With the difference in for example, the contact area between the base of the contact area and the ogive, or the proximity to the rifling, or the type of bullet copper or the conventional lead core can cause pressure variances which may or may not be safe.

Be very prudent when doing this-----pressure will sneak up on you very quickly as I learned this many years ago before I knew better or had the tools to determine what variables needed to be accounted for when doing this.

 

[reinwood]

Thank you for the advices and information! For sure I will be carefull. I hope this "quest" will occupy the evenings after the hunting season that start in 10 days...