New GSC 338 LRH bullets.

If you were going to buy a barrel for those 285 gr bullets, what twist would you get?
 
The OP caption states '338 LRH bullet', but from everything I read this bullet is not designed for hunting. It does not expand and may not stabilize beyond 500 meters?? It also looks like the twist required to stabilize this bullet would make the barrel a one-bullet-barrel, or at least a barrel for mono-metal bullets only. The twist would be too fast for other types of lead core bullets and probably pull them apart in flight. Am I missing something here?
 
The OP caption states '338 LRH bullet', but from everything I read this bullet is not designed for hunting. It does not expand and may not stabilize beyond 500 meters?? It also looks like the twist required to stabilize this bullet would make the barrel a one-bullet-barrel, or at least a barrel for mono-metal bullets only. The twist would be too fast for other types of lead core bullets and probably pull them apart in flight. Am I missing something here?

Hi azsugarbear. The HV range of bullets is their hunting line of bullets. Didn't you perhaps read up on the SP bullet range? Did you follow the link to the pages in my first post?

Given the advertised G1 BC they are definitely long range bullets. Would love to see what BC's Brian Litz will give them so we can compare apples with apples.

Given the advertised impact velocities and double calibre expansion at these minimum velocities I would consider them hunting bullets. They advertise the following with regards to the 285gr:
Minimum Impact Speed: 1600fps to 1700fps (At this impact speed, the bullet will open to at least double calibre)

And for the 257gr
Minimum Impact Speed: 1200fps to 1300fps (At this impact speed, the bullet will open to at least double calibre)

Yes, the required twist rate to stabilise these bullets is a little tight. But is there perhaps something I'm missing? If I use the stability calculator on the Berger website, I get a stability factor of 1.54 given a 1:9.3 barrel at 2800fps at sea level and 10 degree Celsius. I see for SG of 1.5 the recommend a 1:9 twist.

I would go the 1:9.3 twist that will allow me to shoot other bullets as well.
 
Yes, the required twist rate to stabilise these bullets is a little tight. But is there perhaps something I'm missing? If I use the stability calculator on the Berger website, I get a stability factor of 1.54 given a 1:9.3 barrel at 2800fps at sea level and 10 degree Celsius. I see for SG of 1.5 the recommend a 1:9 twist.


I would go the 1:9.3 twist that will allow me to shoot other bullets as well.

I'm not convinced a 9.3" twist will work. Snipers hide shot a similar bullet weight, I think it was a 295 gr, at 3000 fps with an 8" twist and couldn't hit a car at 1000 yards.
 
I'll be interested in the 257gr bullet. As already mentioned, to tight twist will not work well on other bullets.

Could you perhaps post a link to the sniperhide test? Was this GSC's 309gr SP bullet you are refering to?
 
Your first link takes me to a page on the GSC website that outlines specs for their 257 gr. bullet. About 2/3 of the way down the spec sheet they provide min required twist rates: 7.3" twist if under 300 yds; 9.0" twist if under 620 yds; and 10" twist for targets beyond 620 yds. This implies that with a 9.3" twist barrel your bullet will stabilize (or be accurate) only after about 700 yds. With their heavier 338 bullet, the recommended twist rate is even tighter to get accuracy performance at shorter ranges. To me, this is a huge shortcoming in a hunting bullet. I would need a barrel with a min. 7" twist to stabilize the bullet at shorter distances - making the barrel of little use for anything other than mono-metal bullets.

I will readily admit that I have not studied these bullets in great detail. But again, am I missing something here? Not attacking you, my friend - just trying to understand the advantage of this $2 bullet. The ability to open up at lower velocities would be a major plus, but that remains to be proven.
 
Could you perhaps post a link to the sniperhide test? Was this GSC's 309gr SP bullet you are refering to?

Just google Snipers Hide bullet test. They have done more than one. You might find them all interesting.
 
I haven't tested those exact bullets, but have tested similar weight and caliber GS Custom bullets.

For example, the .338 cal 267 grain SP, I measured as having a BC that was around 30% lower than advertised by GS Custom.

The 232 grain SP was advertised about 20% higher than I measured.

The BC's advertised by GS Custom are calculated using software, not tested. It's my opinion that the drive bands are not properly accounted for in the BC prediction software, and that's what kills the real life BC of the bullets (drive bands).

One important factor with these long solids is using a fast enough twist. You want an SG of at least 1.5 to get all the BC that's possible for a bullet. With long solids, you can be looking at 1:8" twist to get SG's of 1.5+. Very few of the high BC solids will give you full stability and BC in a 1:10" twist, or 1:9.35" twist .338.

Take care,
-Bryan
 
Bryan Litz

Wanting to make sure I understand the math. When you say 30% lower, does that mean a BC of .800 changes to a.560?
 
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