Silencer Saturday #406: Suppressing Picky Hosts With The BOE Mod1

by Daniel Y

Published: November 15th, 2025

silencer saturday 406 suppressing picky hosts with the boe mod1

Good afternoon, everyone, and welcome back to TFB’s Silencer Saturday, brought to you by Yankee Hill Machine, manufacturers of the new YHM R45 Multi-Host Suppressor. This week, we are looking at the BOE Mod1 and how it performs on some rifles that do not like being suppressed.

Silencer Saturday @ TFB:

Two weeks ago, we did a full review of the BOE Suppression Mod1. That suppressor has an interesting design offering both vented and closed front end caps. We also have previously tested changing those end caps on a full-auto Uzi to see what impact that has on cyclic rate. The vented cap reduced the backpressure and resulted in a slower rate of fire.

So, how well does that vented configuration work on guns that are poor suppressor hosts? I have a few guns in my arsenal that are, to be charitable, suboptimal for silencer use. Despite having plenty of other guns that work perfectly well with a can, I still feel the need to get them all to work with one.

To compare the suppressed performance I shot the guns in the suppressed and unsuppressed configurations back-to-back. I fired both of these rifles with the Mod1 in the vented configuration using Fiocchi 150-grain FMJ ammo from the same 100-round box. My Garmin Xero C1 chronograph ( with the very nifty protective cover and screen protector from Annex Defense) was running to see if there was a velocity shift.

Brownells BRN-10

First up is the Brownells BRN-10 retro gun. I reviewed this gun a few years ago for TFB and I love it deeply though it is not very practical. Anything with a carry handle is fine in my book, and it is a light .308 with good iron sights that is fun to shoot.

I also love a gun that blends historical interest with usability on the range. This is not a museum piece that should be preserved. It's a shooter. It has pulled duty as a camp rifle during elk season. You know, the kind of gun you keep around just in case an animal happens to wander past while doing camp chores or visiting the latrine.

But the BRN-10 is a very poor suppressor host gun. The AR is known to push a lot of gas back into the receiver thanks to its gas impingement design. Modern evolutions often include adjustable gas blocks or venting methods to keep those gases from hitting the shooter in the face. Neither of those features are available on the BRN-10.

The gas issue is extra pronounced thanks to the charging handle design. Unlike the modern AR, where the charging handle latch is at the rear of the receiver, the BRN-10 uses the original-style upper with a charging handle inside the carry handle. But that design leaves a clearer path for gases to hit the shooter in the face than the new charging handle. Remedies like gas buster charging handles are not available.

Unsuppressed, the BRN-10 averaged 2817 FPS. At only eight pounds, the recoil is stout but not abusive because it is a straight-line impulse. With the BOE Mod1 in the vented configuration, the velocity averaged 2828 FPS, a gain of 11 FPS. Adding the suppressor cut down the sound but even more noticeable was the reduction in recoil. I do not have a scientific way to measure how much it reduced the recoil but it was extremely effective.

As far as gas to the face, there was none. Other suppressors I have tried on this gun in the past never stayed on the gun for more than a few shots because it was so extremely gassy. Not so with the Mod1. I shot it to my heart’s content. The bolt speed felt similar both suppressed and unsuppressed. The brass ejection was also unchanged, tossing the spent brass at 3-o’clock very consistently.

PTR-91

Another rifle that I enjoy shooting but have had poor luck suppressing is my PTR-91. This copy of the HK-91 has mixed reviews online, which seem to boil down to how many of the correct parts were used to assemble each gun, and if the person doing quality control was paying attention that day. I was able to inspect mine fully before purchase, and it has been solid. It makes frequent appearances in my scope reviews.

But like the BRN-10, this is not a platform that lends itself to suppressor use. Roller-delayed guns cannot be easily switched between suppressed and unsuppressed configurations as is often the case in piston designs. Rather, the locking piece must be changed in the bolt group to change the way that the rollers lock and unlock. Sometimes that also necessitates a change of the rollers if the bolt gap gets out of spec.

Some years ago I changed the locking piece in this PTR to the correct #17 model for suppressor use and use with heavier projectiles (I do love some 175-grain match ammo). But the first time I ran a suppressor I fired two rounds before unloading the gun and removing it. The bolt thrust was so forceful that it seemed likely to damage the gun. The original flash hider went back on the barrel and I forgot about suppression.

But given the success with the Mod1 I figured this was worth another try. The recorded muzzle velocity unsuppressed was 2662 FPS. With the Mod1 that increased to 2676 FPS, a gain of 14 FPS. The recoil reduction was not as noticeable as with the BRN-10, in part because the gun is heavier.

Unlike my prior attempts to suppress this gun, the bolt did not feel like it would destroy the receiver. It felt very similar to the unsuppressed setup. Brass ejection was very zesty both suppressed and unsuppressed. The brass ended up in the same area, but the brass fired with the suppressor was sootier.

Conclusion

The BOE Suppression Mod1 works very well on guns that don’t like silencer use. It manages to make guns cycle like they do not have a suppressor while sounding like they are suppressed. If you have some guns in your collection that have struggled with other silencers, give the Mod1 a look. It might be what you are missing.