APS 338 Raptor, R&D early results

So far no complaints, goal was 3150 fps with 300 gr Berger, looks like that will be more then possible in a 30" barrel and then some. At 3150 fps, brass should last a long time which is another design goal for my wildcats. Brass is expensive, I want my customers to be able to get at least 6 firings per case and preferably +8 firings. More testing coming with pics. Today however is shop time on customer projects which get full priority this time of year.

Evenings and weekends are for my playing!! Unless the wife has other plans!!!:D
 
I may but I suspect it will be to fast in burn rate. I may try some VV N-570 if I can round some up but not overly excited to use a powder that is not easy to get for the public. Whats another 150 fps if you can not get the powder.....

It could be a little fast. I got the impression that it was close to H870. But just speaking with an Alliant rep, he said it's a hair slower than Retumbo. On the other hand, another LRH member is using a max load 100 gr pushing 230 Hybrids in his 300 RUM, while my max load for 210's was 93 gr of Retumbo. Seems to be a BIG discrepancy there? It is a dense powder. It takes up a lot less room in my RUM cases compared to Retumbo.
 
It could be a little fast. I got the impression that it was close to H870. But just speaking with an Alliant rep, he said it's a hair slower than Retumbo. On the other hand, another LRH member is using a max load 100 gr pushing 230 Hybrids in his 300 RUM, while my max load for 210's was 93 gr of Retumbo. Seems to be a BIG discrepancy there? It is a dense powder. It takes up a lot less room in my RUM cases compared to Retumbo.

I have found RL33 is more than a little bit slower than Retumbo & N570.

It certainly gives a good velocity increase in my 338 Terminator, (improved Lapua Magnum) over N570 & Retumbo.

I will be interested to see how it goes in the 375 DCM with the 330s & 350 Cutting Edge projectiles.

Looking forward to your testing it in the Raptor Kirby.
 
I have found RL33 is more than a little bit slower than Retumbo & N570.

It certainly gives a good velocity increase in my 338 Terminator, (improved Lapua Magnum) over N570 & Retumbo.

I will be interested to see how it goes in the 375 DCM with the 330s & 350 Cutting Edge projectiles.

Looking forward to your testing it in the Raptor Kirby.

Does RL 33 have nore temp change then Retumbo ? Thanks for info Joe
 
It could be a little fast. I got the impression that it was close to H870. But just speaking with an Alliant rep, he said it's a hair slower than Retumbo. On the other hand, another LRH member is using a max load 100 gr pushing 230 Hybrids in his 300 RUM, while my max load for 210's was 93 gr of Retumbo. Seems to be a BIG discrepancy there? It is a dense powder. It takes up a lot less room in my RUM cases compared to Retumbo.

If its as slow as H870, its ALOT slower then Retumbo and from what I have seen slower then RL50. I would guess it closer to Retumbo then anything but a bit slower.

If it has a higher density, it really helps get more powder in the case. That may be the real difference over Retumbo and a bit slower. Still, from what I am seeing, it will be to fast for the 338 Raptor but may be MAGICAL in the 338 Allen Xpress.
 
I have found RL33 is more than a little bit slower than Retumbo & N570.

It certainly gives a good velocity increase in my 338 Terminator, (improved Lapua Magnum) over N570 & Retumbo.

I will be interested to see how it goes in the 375 DCM with the 330s & 350 Cutting Edge projectiles.

Looking forward to your testing it in the Raptor Kirby.

That is very interesting to hear its a bit slower then N570. I may have to get some in and give it a try in my 338 AX which sounds very similar to your Terminator. Right now using Retumbo in that one.
 
Well, did a bit more testing this evening with the 338 Raptor. Again, sorry, no pics yet, just trying to figure out where this thing is going to end up with different powders and bullets.

In my 338 Allen Magnum, I have had very good results with the 265 gr LRX bullet from Barnes. In the 338 AM, its pretty easy to break 3500 fps using a heavy dose of H-50BMG. Ballistically, no it will not match the berger but its **** close. In fact out to 1500 yards, its drops are dead on the money with the 300 gr SMK in drop and within an moa in wind drift.

So, just for curiousity, I wanted to see what it would do in the new 338 Raptor. This bullet is nearly the same length as the Berger 300 gr OTM and in my testing has a BC in the .650 range when loaded to +3000 fps.

Will not bore you all with another big list of numbers. Simply put, tested with RL50, WC860 and US869.

LR50 topped out at 3345 fps with 130.0 gr. load seated to 4.200" OAL which is roughly 70 thou off the lands. 128.0 gr averaged just a hair over 3300 fps and with very comfortable loads.

WC860 just is not a good match with this bullet weight. I ran out of case capacity at 137.0 gr and was running 3276 fps. No pressure signs at all so this tells me this powder is just to slow for this burn rate of powder. There is bad and good news to this. Bad news is that this powder is very affordable to get in bulk so was hoping it would work better for all around use in this chambering. Good news is that it appears that it may be nearly perfect for the 300 Raptor with a 230 gr OTM or 240 gr. SMK.

Hodgdon US869 is quickly becoming the go to powder with the 338 Raptor. 135.0 gr. topped out at 3410 fps with what I would call max loads. I preferred the 134.0 gr load which averaged 3370 fps with extreme spreads in the 29 fps range. Not amazing ES numbers but plenty usible. With sorted bullets I have found anything under 40 fps is plenty tight in velocity for big game hunting even out to 1500 yards. Obviously we all want single digit ES numbers but in reality, its a good way to burn up a barrel trying to look for greener grass. Most can not shoot from field conditions consistently enough to be able to tell a 30 fps ES down range anyway. I know I can not from field positions.

So far, US869 has averaged in the low 3200 fps range with the 300 gr OTM and just under 3400 fps with the 265 gr LRX bullets.

Next step is to get these loads up to the range and see what they do down range.

On paper, out to 1500 yards, drop numbers are nearly identical between these two loads. Wind drift is about 10% in favor of the berger as is retained velocity. As ranges increase past 1500 yards, the big Berger gains more of an advantage.

At ranges under 1000 yards, the 265 gr shoots flatter and bucks the wind at least as well as the big berger. Plus, at ranges in the 300-800 yard range, it will offer much more integrity for hard impacts on heavier game such as a solid shoulder impact on a bull elk at 500 yards.

I will really try to get some pics soon. Will definitely get some when I get up to the range. have several customer rifles to test this week so will get it tested then after the customer rifles.

Now, if I hold to my performance goals for the 338 Raptor, that being 3150 fps with a 300 gr SMK and roughly 3300 fps with the 265 gr LRX, pretty much every powder tested is showing the ability to reach these performance levels with comfortable pressures. Just another example of how displacement really gets the work done easier then a smaller capacity chambering.

I would prefer to use a stick powder that are more stable over wide temp changes then the ball powders but in all honesty, I have put just as many trophy heads on the wall burning ball powders in my wildcats as I have using the "Extreme" stick powders.

A lot of guys really get nervous about using ball powders but they do have their advantages. For example, when I have been doing velocity testing with my 338 Raptor, using stick powders such as RL50 and H-50BMG, after 3 shots the barrel was very warm and after 5 shots, it was nearly to hot to comfortably hold onto.

3 rounds fired using WC860 and US869 barely made the barrel warm to the touch and after 5 rounds it was warm but I could easily hold my hand on the barrel with no discomfort. I have found this with all of my wildcats ranging from the 257 Allen Magnum, 270 Allen Magnum, 7mm Allen Magnum all the way up to the 338 Allen Magnum.

It is true that if you hunt in a very wide range of temperatures, you have to take special precautions when using ball powder. Best thing to do is either load up a hot weather load and a cold weather load with a drop numbers set up for each.

Or, you simply do your load development on a very hot day and get a good safe working load in hot temps, then when the temps cool off, simply take some chrono readings and record your velocity at the cooler temp ranges and live with the 50-100 fps drop in velocity which really in the scheme of things is not much to worry about.

The main issue with using ball powders is that you need to make sure you do not develop a load to the red line of pressure at 40 degrees and then wonder why your bolt locks up when you take the same load out when its 90 degrees and fire the rifle.

We will see how things work out on the range. Today I was shooting in 90 degree temps and had no problems at all. Of the 25-30 rounds fired, there were around 6 that had noticeable ejector rings on the case head that were showing more pressure sign then I like to see but not a single primer had a primer pocket loose to any degree that I could tell. Very happy with that. The big case is showing it can produce the velocity in hot temps with good pressures.
 
R-33 is pretty slow. I get 80fps more velocity for roughly the same pressure as Retumbo and N-570 in my 6.5-300wm. I just haven't had a chance to test for temperature sensitivity. I use 3 more grains of it to get there too.
 
That is very interesting to hear its a bit slower then N570. I may have to get some in and give it a try in my 338 AX which sounds very similar to your Terminator. Right now using Retumbo in that one.

Kirby you will love it, as long as it doesn't have any nasty traits....
I don't have enough to do much testing with it.
 
If its as slow as H870, its ALOT slower then Retumbo and from what I have seen slower then RL50. I would guess it closer to Retumbo then anything but a bit slower.

If it has a higher density, it really helps get more powder in the case. That may be the real difference over Retumbo and a bit slower. Still, from what I am seeing, it will be to fast for the 338 Raptor but may be MAGICAL in the 338 Allen Xpress.

Just weighed out Retumbo and RL33 using a once fired 300 RUM case to the mouth.

RL33 115.9
Retumbo 112.0

I may be missing something here, but I think it's a good bit slower than Retumbo and on the upper edge of some of the powders you are playing with.

Anyway, if you are having a hard time locating some 33, I would gladly donate some to the cause. I was lucky enough to get an 8 lb jug earlier this year and could easily spare a pound or so. You would just need a way to get it up there from Bozeman.

Looking forward to the pics :)
 
Thanks for the offer, I have access to 1 pounders but have been waiting for 8 lb kegs, Guess I just need to order in the 1s and give it a go.

Thanks for all the information guys.
 
Was supposed to have some local customers come to the shop this morning but on the way to the shop I got a text that they were not going to be able to make it so I loaded up the gear and took a couple customer rifles and the 338 Raptor LRSS up to the range. It heated up fast so did not get to get a lot of work done on the Raptor but a good start. The most consistant loads were with RL50 loaded to an average velocity of 3182 fps.

The loads loaded with US869 showed a bit more pressure on the range then I wanted. These were loaded to 3228 fps tested at the shop and on the range they were averaging 3253 fps which is just hotter then I like. I believe I can tone things down slightly and still make this powder work in cooler temps and still hold 3200 fps, in fact at 3200 fps, pressure are quite mild.

Again, RL50 so far is taking the lead but also want to try some RL33 and see what happens. I think it will be to fast in burn rate but we will see.

I shot today at 1790 yards. Only shot a few three shot groups of each powder but the rifle was easily holding well under 1 moa with all loads and the RL50 loads were ranging from just slightly over 3/4 moa to just under 3/4 moa. The mirage and air quality were pretty bad so I was happy with the start. All would have easily hammered a whitetail at that range cleanly through the vitals.

Anyway, wanted to get some pics posted.

DSC00539_zps04648cf1.jpg


Pretty simple, Raptor LRSS rifle with adjustable A-5 tactical stock. Single shot platform. Leupold MK4 FFP 6.5-20x 50mm w/ TMR reticle.

DSC00538_zpsf152af96.jpg


DSC00537_zps68561172.jpg


DSC00541_zps6d4a3162.jpg


On the left is the 338 Raptor loaded with the 300 gr berger to 4.320" OAL. The round on the right is the 338 Allen Magnum loaded with same bullet to an OAL of 4.280", both rounds have the bullet seated to the base of the case neck. You can see on the Raptor case that the neck is very short, actually, its WAY shorter then production rifles will have. This is because of an oversight I had when I sent the reamer specs to the reamer maker. Raptor brass is 0.080" longer then the brass in the picture, have to trim it very short to fit the prototype chamber.

Reamers are already being corrected as you read this but wanted to get bullets in the air and get testing done.

Much more to come.
 
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