I had a custom barrel made for my 270WSM 28" barrel with a 1:7 twist. I also had the free bore extended so I could have the bullets pushed out so that the bullet did not interfere with the powder charge. It was a tac driver with the 175Gr pill. Nice video bud!

Excellent. Reloading Weatherby did 165gr in 270win with good results. That 90gr Barnes would be a whitetail killing tool. Fast and light recoil

Really interesting vid. I tried stabilizing the 170 Berger out of my 270 wsm and failed. Admittedly I was pushing them a lot faster than your test vid. I noticed your velocities were quite low and if you’ve used similar loads for the other heavy for cal projectiles that you successfully stabilized this would have contributed to the success. The SF considers the distance between center of gravity and center of pressure. The distance between these two directly affects the stability requirements of each projectile. Velocity adds to this also. The more velocity, the more rotation required. Other thing that is worth considering would be how the BC would be effected down range at the same velocities with different spin rates considering how “yaw” can effect a bullet. Going down a rabbit hole now. Great vid, we can all learn from content like this.

I'm glad to see more with the 270 wsm .

I love my 270wsm with 1-8 twist. Pushing 170g Berger Elite at 3200 fps.

Bullet gyroscopic stability can be predicted with mathematics. Math is cheaper than bullets and powder. The gyroscopic stability formulas take into consideration the bullet velocity and the air density due to altitude, temperature, and humidity. The accurate formulas require the transverse and rotational moments of inertia of the bullet… but unfortunately the bullet manufacturers do not publish this basic geometric information so we are left with only simplified approximate formulas like the Miller twist rate formula. The miller formula assumes the entire bullet is homogeneous. As a result, Miller under states the stability of plastic tipped bullets. Fortunately, there is a modified Miller formula available that attempts to account for the stabilizing effects of the plastic tip. It would be very interesting to run the modified miller numbers against your test results to see what stability factors this formula predicts. A stability factor of 1.0 predicts the onset of tumbling. It is wise to try to keep the gyroscopic stability above 1.2 The folks that derived the modified miller formula were able to demonstrate with limited testing that below 1.2 the bullet can begin to experience increased drag due to more wobble in the precession cycles. This basically causes your ballistic coefficient to become variable depending on MV and air density. The folks at Applied Ballistics and at Berger bullets have suggested that it is good practice to maintain a stability factor above 1.5 for long range shooting applications especially if you pass through the transonic zone and go subsonic. The published twist rate requirements on bullet boxes are conservative in an attempt to produce stability in worst case conditions such as low temperatures at sea level. If you are running long bullets at twist rates below manufacturer recommended it is wise to be mindful that you can experience stability at higher temps and higher altitudes but then lose stability at lower temps and lower altitudes. And if your bullet is stable but getting close to the limit you can experience variable amounts of increased drag which can make drops difficult to predict with your ballistic calculator because your BC is changing with changes in altitude and/or temperature. Cheers!

95 gr TTSX out of mine. RL 17 gives McGowen 24” barrel 3950 fps. Great yote load. Love it for deer, (never recovered a Barnes yet). Moose would be interesting to see if the 95 gr could be recovered?

In my 270 WBY with a Barnes MPG ( 85 gr ) I a shooting 79 gr of H 450 . Am getting 3/4 in groups . I haven’t chronographed it yet but will do so soon !

Great video I enjoyed it look forward to seeing more 👍👍

Good video bro., I enjoyed watching your experiment!

Long live the 6.8 Western!!!

Recently, i did a powder and bullet test. I used federal brass, cci primers, Nosler 170gr bullet, and v N-555 powder. This was loaded in 270 win, 22" barrel, 1-10 twist. I had great results, at 100 yards it was .75" group, and chrono'd 2600 fps.

Thanks for your input I don’t know how to reload but really like your videos I to love my 270 WSM

Great video as I've never seen unstabilized bullet impacts on paper, awesome

There you go, now we know. Keep up the good work.

My .270 win will stabilize those 175gr bullets! It's an x-bolt westerner with a 1-7.5" twist 24" barrel. Good test, want to try out some 110gr ttsx bullets, Barnes says 3,500 fps but that sounds hopeful, thanks.

I have a 270 WSM in a Browning A bolt medallion. I run a Nosler partition imr4350 Max Nosler load data loads. I get sub MOA accuracy. My primers are flat but my brass doesn't appear to stretch much and my bolt cycles smooth and gentle. I'm done hunting for a load for it.... I have 140 150 acuubond to partitions but I don't see a need to even work a load up when I get this group with the 130. ( I DO have bigger guns if I want more power).

Makes the case for our Friends at Hornady for the 6.8 PRC. Or fast twist 270s.

Love my tikka 270 win would like to try the heavier bullets like you did awesome video

You will see a difference with temperature insensitive powders …I switched all powders and have way better results cheers and happy shooting

The beauty of the 270wsm is in those extra 200 fps over the 270 win with the 130 - 150 grain bullets. Wouldn't trade speed for bc. in a hunting cartridge. But stabilizing those 165 grain bullets add versatility to the cartrdige. Would be interesting testing those high bc bullets on a 270 winchester too.

Great job, great to know ! I still need to reload the 162 grain copper impacts pulled from my 6.8 western in my 270 Winchester, to see if I can get them to stabilize at 4500 ft elevation.

Neat test, thanks for doing this. .270 wsm seems like a great round, but definitely need to be a reloader since ammo is so expensive.

I've used 110gr 270wsm for Whitetail's it's a very effective load! I will be following your footsteps and loading the 165gr for a test! I feel like rubbing Winchesters nose in this one! They can keep that 6.8 western

I night be interested in those gamekings. I haven't been able to find factory loadings for my 6.8w with the gamekings and am going to start dabbling in reloading this year

Nice muzzle flash.

That's nice rifle I budget to pick up one in 243 even though I'm not the reloader I'm still enjoying your channel

Great video.!! Thanks. I have both the 270wsm and the 6.8 Western, both NIB. I was not planning on going any higher in bullet weight than 165gr in my 6.8 western. Now it seems like I wasted my money buying it because I can shoot the 165gr from my 270wsm. Actually, the 6.8 wasn't a waste of money.. I'll admit, I like to buy guns.

I’ve got a 270 win 7.5 twist. I haven’t tried the tipped game king yet, I’ve been shooting the 170 Berger

Maybe trying different powders might help

The analogy with a tire being out of balance only works when talking about bullets that are not concentric. It's not necessarily the cartridge that determines stability, but more so the barrel with its twist rate. Velocity will help some, but not as dramatic as rifling twist.

I think I saw the new browning rifle has a 270win with 1-8 twist. be interesting to test with these heavy pills.

My 270 wsm shoots the 140 grain nosler partitions best. 3/8" group and less if I do my part.

I found my 270WSM would not stabilize the 165 Nosler LRACB. My 6.8 Western likes the 175 Gamekings

This certainly was a fun video. What grain bullet do you normally hunt with in 270 WSM?

I used to use 4831 IMR in my wsm Browning a bolt 2. It shot really well not sure.of velocity. At that time I didn't have chromo to see but 4350. Wasn't anywhere near as good shooting as 4831. Hands down better. But with 140-150gr bullets. Lol

Almost sounds like in the first group, one cows got hit…..

Was curious what twist rate your barrel is?

I tried heavy bullets in my 22-250 once and I couldn't hit the side of a barn with them my pet load for my 270wsm is 65grs RL19 behind 130gr barnes does under a inch at 200 yards

Them loads were ridiculously light , and it not true that speed will make it worse, using the tire analogy yes it gets worse but then if you go fast enough it will suddenly go away and get better

Awesome video! I think you found the limit lol. I’ve been so curious about this.

Great round.. to bad you cant get brass for it.

whats the twist rate in your rifle.................. that has a major factor in stablity

Different speeds Different twist rates and grain bullets

What cartridges are these heavy .277 bullets made for….6.8 Western?

Experimental pew pew scientists that's who we are great video

If I were you, I would sell the 270 WSM and buy a 6.8 Western. We must save the 6.8 Western!😅

Odd to me everyone talks about twist rate, and how unstable bullets become, not a soul says a word about 30-06, and it shoots 110gr to 220 gr without a problem with a 1-10 twist.

Also that Chrony is basically useless for standard deviation calculations as the margin of error is too far out. Shoot with it in-line with a dopler chronograph on the same shot strings and you wont even consider the accuracy worthy of the word. Others have done so and the Chronys just aren't accurate enough for ladder testing or really any meaningful analysis.

Why such low speeds

I wouldn't be too quick to trumpet the previous marginal stability. Even if the bullets are only out a small percentage they will not function properly when hunting if off axis. Not to mention if your variables like weather change and push it over. No reason to flirt with the edge and then wonder why you fell off despite all your edge riding practice. If you want to shoot long bullets .277" isn't the right choice (6.5 and 7mm both have better options).

Bullet length...that is the question.

85g to 165 g...seems legit to me

Why try to shoot too heavy for caliber bullets? The 270 WSM is very effective with 130 140 grain bullets. If the hunt scenario calls for a heavier bullet, increase the caliber, not the bullet weight. If it's not recommended, who cares if it "shoots" or not?

🕵️‍♂️ Even If The 175 Grain Bullets Would Have Stabilized, At Those Velocities The 165 Grain Bullets Would Be The Better Choice! For That 175 Grain Bullet, The 280 AI Would Be A Much Better Choice! 🤑

I think your charge is either too much or too little. 2400fps is too slow.