Barnes 200 grain .451 XPB FB

[rangeball]

Anyone getting accuracy with this bullet saboted in a .50 barrel? What powder/sabot at what velocity?

I assume no expansion problems at 2500 FPS down to around 1200 fps or so? Anyone no the lower FPS limit to get good expansion?

Assuming it can be flung accurately at 2500 fps, it would be +/- 2.5" out to 200 yards.

Thanks

[E.T.]

Acquired a nice supply last year but got kyboshed for range time when the infinite wisdom of our politicians made a ruling of having a 3-side 14ft berm surrounding the range. Of course my 2-favorite ranges were shutdown. Should be up and running in the spring.

I have a reasonably tight bore and still had to cannelure/knurl the 200XPB’s in a Harvester RCR sabot to first get the resistance fit I sought.
As for results of accuracy and velocity will let you know when I get a chance to try them.




Ed

[rangeball]

Excellent, praying for range time for you soon

[E.T.]

Rangeball

There is another sabot that will produce a good fit and that is the knight sabot. This sabot has a little softer plastic construction but suspect that it might not generate the velocity and accuracy level I seek. But in all fairness I plan to give it a try also with a different approach by using a sub base with the head trimmed off flush and trim off the cup of the knight sabot leaving a flat base. Sort of a 2-part sabot with a stronger cup base.



The only other problem I see with the softer plastic construction of the knight sabot is quicker fouling of the bore. For plastic fouling I plan on trying a product mentioned a few years ago here to help with reducing plastic fouling. Should get it in the mail sometime next week. Another little test to tag on here for results.

Hope to start testing sometime by late March.

Ed

[rangeball]

Ed, would the standard hp12 or hp24 from MMP be up to the task? I had assumed, probably wrongly, that since the 250 and 300 barnes bullets of the same diameter shot well from the MMPs that the lighter bullet would too.

Or is it a function of the higher velocity causing the sabot to fail? Since they apparently hold up at 2300 fps, I had assumed they would only 200 fps faster, but maybe not?

[DW]

The RCR will give the tightest fit. These bullets have a small bearing surface plus they are only .451 in diameter. I got them to the point that they loaded with similar resistance to the 250SST by knurling and using the RCR.

Best I could get out of them was 5" at 200yds and it was tough getting this combo to 2600fps in the Savage.

[rangeball]

DW, what was tough about getting speed with these? Blown or distorted sabots? Or finding a powder that worked well enough?

[DW]

Powder. The bullet is so light I could not get a good burn with straight( the muzzle flash was blinding in broad daylight) or duplexed H4198. An N120 duplex like the one used by the guys when they were experimenting with the .40 200SST probably would work better

[rangeball]

Thanks. Hopefully by the time I get my SMI barrel, Ed will have it all figured out for me

I noticed Ed clipped the petals on the RCR. What's the general rule, clip them to just below the ogive?

[richard]

I would clip them just at or slightly above the ojive. The main reason for clipping is so your jag does not get caught on them.
Richard

[PPosey]

Sabotless anyone?

[E.T.]

Rangeball

Richard is right about the primary reason for trimming sabots. But I also find this helps a little with groups and accuracy with my setup. Others say they don’t find a difference with trimming. Sort of like one setup may work for one person but not for another.
If you decide to trim then getting the petal lengths consistently even with close as possible to 90-degree trim is important IMO.

Jan 1, 2009 11:30:28 GMT -5 PPosey said:

Sabotless anyone?

Interesting 2-word question directed at a 50cal thread using sabots.
Wonder what kind of response you would get from the guys using sabots with the 45 or now the 40 that has a sabot candidate?


Ed

[chuck41]

With the 40 trimming the "sabots" will be a necessity, not an option. Without trimming those things could be tied in a knot in front of the bullet. A 410 wad is really long!!

[SW]

For a 200g bullet, I'd consider 46g-48g+ of 4759 or VV-110 and then, if it shoots(likely in the 2500+'/sec range), consider a duplex if higher speed is desired.

[PPosey]

Wasn't trying to be a smart butt,,,,, just saw that Barnes 200 grain .451 XPB FB in the image and thought wow that should resize easy to .4495

[wilmsmeyer]

I had very good luck with .451 185 gr XTP's with a duplex of 30/60 4759/322. Over 3100 fps with MMP shorts. Not MOA but under 3 inches @ 100 yds...no fliers.

THEN...I tried a very similar duplex with the bullet discussed in this thread. Same sabot. Did not chrony but got horrible sabot failure. Did not spend a lot of time as I wanted this bullet fast or nothing.

Used the rest of these bullets with 70 Gr FFFg in my .54 Thunderhawk for my girlfriends first year deer hunting. They shot decent out to 100 yds. FWIW

[E.T.]

PPosey

Now that the intent of that question is revealed I’ll take it as that.

Wilmsmyer

In the past before I found this board I used 47gr of 4227 with the 200xtp (.451) and shot my first deer with the 10ML-II. Just a nice 60-70yd shot. I was getting 1-1/4” groups at 100 but didn’t have a Chrony at that time. Since then I got quite the education from this board including using 4227.
The 200XPB if taken to 2650fps will have over 1000ft/bs at 200yds and 2” less drop that my current 250gr book load, according to my point blank calculator. I’d be happy with this less recoiling load if the accuracy is there for my 200yd limit of shooting. Will find out this year for sure as its first on my list for my next range visit.

I can also see that with a duplex a much higher primary igniter is needed to get the initial pressure to flare the sabot base and generate a good burn. But first time around I want to try with 4759 up to 49-50gr max. My approach would be the ladder method but using 2-shots instead of one.
I ‘ve had to wait a long time to try this and look forward to seeing results on paper.

Ed

[rangeball]

Thanks everyone

Ed, sounds like you and I are on the same page. If this load will shoot 2 moa at 200 yards, I'd be very happy with it where I hunt. Really looking forward to reading about your testing when the time comes

[E.T.]

Rangeball

In case you get antsy and want to run your own experiment I thought I would pass along some of my thoughts on my approach.

1) A good snug fit is essential combined with a faster powder to flare the sabot base to get this puppy flowing out of the bore at a good speed.
2) For good stabilization a consistent RPM will be needed. The 200XPB has minimal bearing surface for sabot to bore contact. Here in my opinion knurling would in all likely-hood be a must.
3) Again for good stabilization for our 10ML-II application of 200yds a useful muzzle velocity in excess of 2500fps will be needed. Just an opinion as results on paper will confirm this or not.

Others who have tried this have had good results at 100yds but from their experience at 200yds it became what I call a crapshoot. Accuracy deteriorated drastically for them. To try and prepare for this event I have wondered what could be causing this condition.
Is it RPM stabilization through a velocity range?
Is it due to nose length to body length ratio?
Or is it something else that I will hopefully stumble across?

I look forward with eager anticipation to start testing in the Spring where temps will be in range for my hunting conditions. If I can get this puppy to perform reasonably well with groups 2” & under at 200yds like my 250SW then I have a winner.

Regardless of outcome I will post my results.


Ed

[mshm99]

ET

MMP sells sub bases at a reasonable price ,if you are inclined to go that way. Mates up to the bottom of a mmp sabot perfectly.
mshm

[rangeball]

Thanks Ed. Unfortunately, I'll be bringing up the rear as I've yet to call SMI and order my barrel. I can't until I'm done hunting with the H&R I plan to convert, which won't be until the 19th. I may go ahead and call them to see if I can just send them a deposit or something, as Ron said it would take 90 days as they'd have to order the barrel from douglas with the 1:22 twist rate I want. I'll also have a 28" barrel to work with, which should be a plus.

Can the knurling you mention be done with rolling between two files, like many do for up-sizing purposes?

[E.T.]

Rangeball

Going with the 22-twist should be a bonus for RPM stabilization, as you will produce a faster RPM for given velocity than the Savage 24. Also should see less fouling if any with a quality barrel compared to the rough Savage bore.
Never used a file for knurling with all copper bullets but don’t see why not. The trick will be doing it consistently for the same proper fit to the bore. As I already have a canneluring tool this does the job nicely with multiple cannelures set for a specific depth.
Will look forward to seeing how you like the Douglas barrel as I have contemplated on getting one to try. I know the guys here are doing dynamite with the 40 & 45 calibers opening new doors and heights for muzzle-loading but I still have a love affair with the 50.


Mshm

Appreciate your trying to help with this suggestion for using a MMP sub base, which I have tried in the past with other loads. They didn’t perform well with my setup and suspect the extended nose from the mmp sub base was heel kicking the sabot when separating. That is why I want to try some loads with that sub base nose trimmed off and a sabots cupped base trimmed off for a flat fit. What got this idea going was from another shooter that mention that the only way he could get his 250gr sabot load to shoot good was with the addition of a 28gauge wad (petals trimmed off) under his sabot. But this is another experiment in itself I want to explore.


Ed