36 Grain Sinterfire and 27 Grain SS195 from .223 Rem

[Wollychop]

Well, a bit of a continuation here. Fired from a Remington 700, 24" Bbl, 1:12 twist.



Tested another batch of 36 grain Sinterfire bullets with a different chrony placed further from the muzzle, about an extra 5 feet or so. I think Grantness hit the nail on the head with his analysis that the jacketless rounds allow gas to escape past them. Here's the new data:



Powder: H322 (23 Grains)
Bullet: 36 Grain Sinterfire
OAL 2.238

Velocities
3254
3176
3235
3221
3216
3299
3280
3348
3282
3308

You'll notice that the velocities have a pretty fair spread. I was very careful with consistency and my other reloads I fired stayed within 30 FPS (with the exception of the pulled SS195s), so I think this is a characteristic of the bullet. HOWEVER, the bullets are quite accurate for the money and I have no complaints where that is concerned.

To top off the sinterfire adventure, we shot at three milk jugs filled with water back to back, to see how the penetration was.

The last shot at 3308 FPS exited the first jug in fragments. The second jug had multiple entries and a very nasy exit where most of the bullet's mass exited in a variety of directions. The third just had a few tiny entries, almost pin pricks, and I recovered one small piece of the bullet in the third jug. Looks like they work as advertised, as the round fragmented dramatically.





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The SS195's projectile was very disappointing. Someone may have more luck with this than me.

Velocities on a 23 grain charge of H322:

3471
3374
3436
3405
3402



Accuracy was terrible. I don't know if this is an effect of the rifle or of a bullet not designed to fly at these velocities, but you can see by the picture that the rounds, fired from a bench, were all over the target. No evidence that they lost their jackets or anything of that nature, however the points of impact were all over the place.



I'm going to try these same tests next weekend using a couple varget recipes, and I expect better velocities, but I don't think the 27 grain BTHP round from the SS195 looks promising from a .223 remington.

[Grantness]

Nice report! :thumb: Im curious about the mutiple entry holes with the Sinterfires. Do really think the sinterfires broke up as they hit the plastic and spread out before entering the jug? Or do you think they broke up in the barrel or in flight?

Im pretty sure the charge was too low for the 28gr bullets. 25.5gr is listed as the max for H322 and a 40gr jacketed bullet. A 28gr bullet may need a considerably higher charge. It might be hard, but Im sure you can find data somewhere for 30gr VMax's or Bergers for .223, and use that as a starting point.

[Wollychop]

Nah I don't think the sinterfires break up in flight, the holes they leave in the paper are too clean. I think they come apart in the water in the jug. The round entered the first jug, broke up and left multiple entries in the second. The second jug actually had the worst damage.

The starting charge for a 40 grain bullet for H322 according to Hodgdon's reloading center is 23.5 grains. I wanted to start reasonably low, especially since I am only doing these pulled 195s 5 rounds at a time (since I have a limited number of them).

Since 23 grains pushed the 27 grain rounds at over 3400 fps could you really could claim that it was an insufficient amount of powder? I'm not saying that you couldn't go quite a bit faster -- I have no doubt you can -- but if they aren't flying straight with a 3400 fps muzzle velocity, what's it going to take?

http://data.hodgdon.com/cartridge_load.asp" onclick="window.open(this.href);return false;

I don't have any problem pushing them harder to see what happens. No signs at all of pressure.

I'm probably going to push the sinterfires in the next batch at 25 grains and the 195 bullets at 25.5 and see what happens.

[gw45acp]

I have a Chrony F1 Master and muzzle blast has caused me problems, but never like what you experienced. Wolly, do you have a remote switch for your Chrony to cycle through the data and shot strings? I made one for mine and it sure makes things easier. Oh, and thanks for posting your follow up data.

[romer522]

Barnes claims 3876 FPS on the 36gr VG out of a 24" barrel with 29.5gr of TAC. Load density of 99%, so you could probably just fill a case up with TAC and see what you get with the 28gr (JK, well mostly)

[Grantness]

Nah I don't think the sinterfires break up in flight, the holes they leave in the paper are too clean. I think they come apart in the water in the jug. The round entered the first jug, broke up and left multiple entries in the second. The second jug actually had the worst damage.

The starting charge for a 40 grain bullet for H322 according to Hodgdon's reloading center is 23.5 grains. I wanted to start reasonably low, especially since I am only doing these pulled 195s 5 rounds at a time (since I have a limited number of them).

Since 23 grains pushed the 27 grain rounds at over 3400 fps could you really could claim that it was an insufficient amount of powder? I'm not saying that you couldn't go quite a bit faster -- I have no doubt you can -- but if they aren't flying straight with a 3400 fps muzzle velocity, what's it going to take?

http://data.hodgdon.com/cartridge_load.asp" onclick="window.open(this.href);return false;

I don't have any problem pushing them harder to see what happens. No signs at all of pressure.

I'm probably going to push the sinterfires in the next batch at 25 grains and the 195 bullets at 25.5 and see what happens.

Oops, I thought you said the first jug had multiple entry holes from the sinterfire... my bad.


The charge was too low for the 28gr SS195 bullets from a pressure/velocity standpoint. Usually, other factors have a greater effect on accuracy. I doubt you have enough bullets to spare, but what you would want to do is play around with the seating depth, the charge, check bullet run-out, and even try different types of powder. Did you crimp the rounds? ...and of course there's the fact that these bullets arent the most consistent I've seen. The bullet OAL and weight can vary significantly. For best results, you'd have to sort them by weight and length. That being said, your groups were still way larger than you'd get from a PS90. Something else is going on for sure...

Your Rem 700 has a 1 in 12 twist. The P90 has a 1 in 9 twist. However, you'd think the extra velocity would make up for it. I certainly havnt had any accuracy issues with my 1 in 12 twist T/C. One possibility you may have to consider is that w/ the added velocity there is too much spin. I once read in an article from a respected ballistics writer that too much spin on a bullet can cause it to wobble around for the first 100 yards or so before "going to sleep". I'll see if I can look it up for you... The problem is, this bullet isn't exactly going to win any long distance shooting contests. Its so light that it loses all of its energy in a hurry.

Maybe try shooting them out of a different gun. You never know. Some guns just hate certain loads.

[Wollychop]

Oh believe me I hear you. I chose a seating depth based upon the throat length of the remington. Backed them off just a **** hair off the rifling. Used lee's "factory" crimp die.

I'm gonna play with it more, just a disappointing start ya know? Very possible that the powder / bullet combo is a bust. H322 is not at all ideal for .223, but it's what I have the most of! I think that I am going to take Romer's advice and pick up some TAC since it seems to be in stock just about everywhere and give that a whirl with the bullets.

I would love to hit a sweet spot. I think it would be a real fun critter buster.

[romer522]

:lmao: Shows my reading comprehension, i just skipped over your post and looked for the numbers. Just now realized you were using a bolt gun not an AR.

4k FPS ought to be completely possible from a bolt gun. Though you might run out of case capacity with TAC before you hit 4k.

[gw45acp]

I've used both TAC and Exterminator for .223 with good results out of a Remington SPS, but I used nothing lighter than 36 gr. Varmint Grenades. Those loads consistently grouped MOA at 100 yards. First of all, I would not crimp these for use in a bolt gun. There really is no need and you will likely hurt accuracy by doing that. It can distort the bullet and create less than even neck tension between rounds. Since it was pointed out that these can be shot out of a PS90 with 1:9 twist more accurately than your first test out of a bolt gun, it is not likely that bullet run out has anything to do with it.

I think the big factor is the twist rate of the Rem 700 in relationship to the weight and bearing surface of the 28 gr. bullet. Even though twist rate is the best rule of thumb for selecting the proper bullet weight, the bearing surface also enters into the equation. The 28 gr. bullet has significantly more bearing surface than a 36 gr. VG or 40 gr V-Max. This could cause it to have stabilization characteristics similar to a heavier bullet, but not to the extent that you are getting any keyholing. I know you have a limited supply of test bullets, but you should see if the accuracy improves at 150 or 200 yards where the bullet has more time to stabilize. As Grantness pointed out, these aren't exactly match grade bullets.

[Rapier1772]

:lmao: Shows my reading comprehension.