Suppressors Thunderbeast Arms 338 BA question

[jaycoux]

So I have this friend who just bought a 338 BA for his TRG 42. Having great success with my TBAC suppressors I naturally recommended them to him.

He asked them to send off the brake before the paperwork for the suppressor was approved so that he could get it on the rifle and start shooting with it.

He tried it out yesterday and got some weird results. From what I saw his groups were about 2 inches, repeatable, with the same pattern at 100 yards.

Several thoughts crossed my mind-

1. He is a poor shot-No, he routinely shoots well at 1000 and his groups are usually respectable, always under 1 inch, usually much less than that.

2. He made some sort of mistake while installing the brake-Maybe, I don't know. The installation is not as simple as just screwing it on apparently.

3. Can the addition of a different muzzle brake (He was previously using my factory Sako brake) cause a once reliable load to become horrible?

Of course, a phone call to TBAC is warranted, but in the meantime, any feedback would be appreciated-

jay

 

[KYS]

Re: Thunderbeast Arms 338 BA question

Did he time the brake properly?
Check the end of the MB as he might be getting strikes.
A 338LM is really not meant for 100 yards, I would back it up to a minimum of 300 and recheck the grouping.

 

[Zak Smith]

Re: Thunderbeast Arms 338 BA question

Hi,

Whenever you hang something different on the muzzle it is "possible" that a once-accurate load may become less accurate because the barrel's "node" has changed. However, this is extremely rare and more of an "in theory" thing because I don't think we've ever seen it happen (without something else going on).

If his TRG still has the factory threads, it'd be almost impossible to install a 338BA-Brake wrong and cause baffle strikes. Of course, this should be checked, but it would be really hard to booger up the install. The installation is only "not as simple as screwing it on" to the extent that we provide a peel washer to time the brake and recommend the use of Loctite. We do this so the end-user can install the brake and have it time right instead of requiring a gunsmith to cut on the shoulder to time it (get the top at 12'o'clock).

It is most likely that the instantaneous movement of the rifle is a little bit different from the factory brake and the rifle is recoiling a little bit different from before. For a .338LM, the TRG42 is a relatively lightweight rifle (compared to many customs or an AI), and this may expose technique deficits.

I made some comments about recoil and the "BA" brakes over in this thread
http://snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=3224082#Post3224082

I would recommend checking that the brake was installed properly, that it isn't getting any strikes, and then have someone else shoot the rifle and try some different ammo.

Please give us a call.
thanks
Zak

 

[jaycoux]

Re: Thunderbeast Arms 338 BA question

Many thanks Zak,

I spoke with ray earlier and I think we are going to try some of my trg loads and use my factory sako bipod to see if we get better results.

He also uses a monopod on the rear instead of a bag which I feel is probably causing a lot of his problems, but he didn't seem to be having these issues before. I know he recently switched to smk 300s so maybe that's part of it also. Ill keep you posted.

As always, thanks for your quick reply. I appreciate you guys alot.

Jay

 

[Zak Smith]

Re: Thunderbeast Arms 338 BA question

As more info trickles in it sounds like there is more going on that just a change to our brake.

If he changed from 220's or 250's to 300, he's going to see a lot more recoil no matter what muzzle device is on there, and this makes the rifle harder to shoot accurately.

I agree that the rear monopod is probably causing problems.

 

[KYS]

Re: Thunderbeast Arms 338 BA question

I would say the larger grain ammo and the new brake is what is giving you problems.

 

[Hannibalsnipes]

Re: Thunderbeast Arms 338 BA question

Okay. Guilty party here. I am going shooting w/ Jay tomorrow to try and sort this out. The best info I can add at this point is that the only variable that changed was the MB. Shooting the same load with the Sako brake, I had good groups and the recoil didn't bother me. After installing the TB brake I had bad to decent groups and the recoil was quite bad. I keep pretty good notes on my shooting and after shooting the rifle with the TB MB for the first time my notes read, "not impressed with muzzle brake". I wrote that because I could tell that there was a signifigant increase in recoil (after 1 shot).
Here is a direct grouping comparison: Sako brake- 1.162, 0.737, 0.898, 0.120, 0.901, 1.136. TB brake- 1.403, 2.492, 0.721, 1.863, 1.501, 1.638, 2.041, 0.364, 0.924. Every variable in the equation was the same: temp, time, brass, powder, primer, bullet, wind, rifle, except for the TBMB.
Hopefully we can get some of this sorted out tomorrow. I'll update then. Thanks all for your help and input.
Oh, and I know that the first bunch of groups aren't great, but I've only had the rifle a year, and I've still got a lot to learn.

 

[Zak Smith]

Re: Thunderbeast Arms 338 BA question

In our experience TRG-42's will usually shoot half MOA or better groups with good ammo, using either no muzzle device, the SAKO TRG-42 brake, the BA brake, or our suppressor. About all I can suggest is if that's not happening with your rifle, something else is going on.

 

[Hannibalsnipes]

Re: Thunderbeast Arms 338 BA question

I'm not trying to put anyone on the ropes here. I just dropped 2K on this MB and can, and I'm trying to discern why the recoil and accuracy just both got worse. Jay highly recommended y'all, which I in turn have recommended you as well. (You may recall a much larger than normal order from SniperShop near Austin TX recently).
Ray has emailed me a few times and it's obvious you guys have put way more bullets down range than I have, so I will acquiesce to your experience and acknowledge that I am probably the biggest problem with this poor shooting.
Jay and I will get behind the trigger tomorrow and see what we come up with.
Thanks

 

[Zak Smith]

Re: Thunderbeast Arms 338 BA question

In that other thread about brake performance I wrote,
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">
Brakes like the Badger FTE or the AI .338LM brake have more surface area on the two impact plates because they have a larger overall O.D. However, you couldn't fit one of those inside a suppressor.

Our brakes are good and I think you'd have a hard time noticing a difference between other good brakes on the market for the "target" cartridges-- however, the goal of the "BA" brakes is not just to be a brake: they also have to integrate with the suppressor so the system works well when shooting suppressed</div></div>
The implication of the first quote paragraph is that there are brakes on the market that can reduce recoil more than the 338BA brake; however, due to their size, they would not fit in a reasonably-sized suppressor.

It is well known that a suppressor on .338LM typically will not reduce the recoil as much as the best brakes on the market, although they will smooth out the impulse over time. There is a lot of lead still moving forward and all that gas does have to exit in a forward direction (although it is paused and delayed by the baffle stack).

The 338BA was tested during its development extensively on the 98B, MRAD, AI, and TRG, and accuracy was never affected using the brake.

hope this helps
Zak

 

[stprelle]

Re: Thunderbeast Arms 338 BA question

Not to butt in butt, I'm curious of how hard was the origional brake to remove? Was it red loctited, heat used ect. Mine personally I had to heat and get western with it. Just curious.

 

[Hannibalsnipes]

Re: Thunderbeast Arms 338 BA question

Original Sako brake took about 2 minutes to remove max. No loctite required.

 

[Hannibalsnipes]

Re: Thunderbeast Arms 338 BA question

Jay and I hit the range today, to discover that it was closed for the Texas multi-gun championship; always fun to drive over an hour to discover that. We ended up going to a different and inferior range and due to all the extra driving, had only an hour to shoot. One hour wasn't nearly enough to test all the theories we had come up with, but we did confirm that the accuracy is not due to the TB brake. It's due to me. The only association with the brake and accuracy, is that I've never noticed the reticle moving due to my heartbeat unless shooting at 1000 yrds. With the extra recoil, my adrenaline gets going and I start noticing the reticle moving at 100 yrds after about 5 shots.
Jay made the observation that my loads are too hot, so I need to back off on those a tad. And, I made some adjustments to the buttpad that seemed to help distribute the recoil more evenly.

So, I loaded 40 rounds this afternoon at 88.5 grns which is 1.5 fewer. In another week or two, we'll go back out and test those out and see what we come up with. I am still greatly anticipating getting the can once the form 3's go through. Thanks,

 

[jaycoux]

Re: Thunderbeast Arms 338 BA question

In regard to the initial concerns presented in this post-
1. While I only shot 4 rounds of the 300 grain smk's through the trg with the tbac brake, I did not notice that it recoiled any more violently than my trg with 250 grain scenars with the factory sako brake. They seemed pretty comparable to me.
2. Accuracy issues are multi-factorial, but are not related to the brake.

Regarding the loads-Current powder used is magpro. Inspection of fired cases showed soot around some of the primers, mostly flattened primers and consistent ejector marks indicative of a high pressure load. My friend has some retumbo now, so we will do an ocw with that and find a happy load to use in the future.

 

[Hannibalsnipes]

Re: Thunderbeast Arms 338 BA question

After going to the range two more times and ironing out some of the "multifactorial issues" that Jay mentioned, the accuracy has improved to better than where I was before I switched brakes.
So I wanted to be clear that this Brake does not adversly affect accuracy.
My last outing I shot 20 times and had light and dark bruising the following day. Every group was sub 3/4 inch and some much better.
Jay is thinking that the position of the buttpad is the culprit of the bruising. We'll explore that next time out.

Sorry for the quality of the pics, (phone cam).

 

[Hannibalsnipes]

Re: Thunderbeast Arms 338 BA question

Just wanted to update this. My form 3 finally arrived and I got a chance to use this suppressor. The TB338ba was very impressive. The POI shift was greater than I anticipated, however the recoil and sound reduction were amazing. As far as accuracy, I think that if anything it made the rifle even more accurate. I was shooting 300gn SMK, Lapua brass, 89.0 gns of Hogdon powder.
Range report is as follows: 3 5-shot groups: 0.638, 0.746, and 0.805 for an average of 0.729. Not my best but not bad considering the suppressor caused a huge change in the feel of the rifle.
I'm going to load some 250gn SMK and see if that affects the POI shift.
A huge thanks to the guys at TB for a great suppressor.

 

[dvdt]

Re: Thunderbeast Arms 338 BA question

How's the recoil with the can compared to the original TRG brake?

 

[stefan73]

Re: Thunderbeast Arms 338 BA question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Zak Smith</div><div class="ubbcode-body">In that other thread about brake performance I wrote,
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">
Brakes like the Badger FTE or the AI .338LM brake have more surface area on the two impact plates because they have a larger overall O.D. However, you couldn't fit one of those inside a suppressor.

Our brakes are good and I think you'd have a hard time noticing a difference between other good brakes on the market for the "target" cartridges-- however, the goal of the "BA" brakes is not just to be a brake: they also have to integrate with the suppressor so the system works well when shooting suppressed</div></div>
The implication of the first quote paragraph is that there are brakes on the market that can reduce recoil more than the 338BA brake; however, due to their size, they would not fit in a reasonably-sized suppressor.

It is well known that a suppressor on .338LM typically will not reduce the recoil as much as the best brakes on the market, although they will smooth out the impulse over time. There is a lot of lead still moving forward and all that gas does have to exit in a forward direction (although it is paused and delayed by the baffle stack).

The 338BA was tested during its development extensively on the 98B, MRAD, AI, and TRG, and accuracy was never affected using the brake.

hope this helps
Zak </div></div>

I would say that recoil is probably a big factor. Sako muzzle breaks are very good IMO. I am using them on both my .308 and .300WM. There is more felt recoil once switched to the suppressor, just the nature of the beast.

V/R

 

[dirtyname]

Re: Thunderbeast Arms 338 BA question

Practice, practice, practice. I try not to be quick to blame my equipment.

 

[Hannibalsnipes]

Re: Thunderbeast Arms 338 BA question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dvdt</div><div class="ubbcode-body">How's the recoil with the can compared to the original TRG brake? </div></div>

I honestly can't answer that becuase I put a limbsaver buttstock on the TRG and the recoil was dramatically reduced.

 

[Kino]

Re: Thunderbeast Arms 338 BA question

Hard kicking rifles do make most of us not shoot to our best potential. Lightweight hunting rifles like 300wm seems to have that effect on folks alot! Glad you guys are working out the bugs. How much POI shift did you actually have??

 

[RayDog]

Re: Thunderbeast Arms 338 BA question

I've shot our cans on several TRG 42s. I've had zero to 1.5 MOA shift straight down. I was surprised that on one of my TRG 42s there was no shift with the factory tube even though its so skinny. That was a good barrel. I've shot some crazy small groups from far away with that one. To bad I shot it out.
From what I've seen every barrel is different and the effect of POI shift seems to be barrel to barrel. I've seen others post on here that they have zero shift on their TRGs.

 

[Kino]

Re: Thunderbeast Arms 338 BA question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RayDog</div><div class="ubbcode-body">I've shot our cans on several TRG 42s. I've had zero to 1.5 MOA shift straight down. I was surprised that on one of my TRG 42s there was no shift with the factory tube even though its so skinny. That was a good barrel. I've shot some crazy small groups from far away with that one. To bad I shot it out.
From what I've seen every barrel is different and the effect of POI shift seems to be barrel to barrel. I've seen others post on here that they have zero shift on their TRGs. </div></div>

From what I have learned is that MOST factory threaded tubes are not threaded as concentric as they should or could be. With the 338 cans being long and heavier, this amplifies the barrel harmonics as well. The TRG has a long, thin barrel and most
are factory threaded so I can see where peoples mileage may vary, even with a well made can.

I bought my Sako TRG 42 (338) from Tim at SAS as it was one of his test rifles before he moved shop this summer. I have yet to get it running with a can but already know what to expect with his 338 can, and that is none to very little shift as well.

 

[Kino]

Re: Thunderbeast Arms 338 BA question

I also forgot to add that the TBAC guys have a great reputation for customer service so if there is a problem I am sure they will take care of it.

 

[Hannibalsnipes]

Re: Thunderbeast Arms 338 BA question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Kino</div><div class="ubbcode-body">I also forgot to add that the TBAC guys have a great reputation for customer service so if there is a problem I am sure they will take care of it.
</div></div>
It wasn't a problem at all. Once I adjusted the scope it shot good groups. It made the rifle feel like a competely different rifle and that affects the grouping a bit, but I was very happy with the suppressor.

The POI shift for me was 3.2 inches low and 0.75 inches left. This was shooting at 100 yards.