By partially deflecting to the bump-stock questions, the NRA (and its supporters in Congress) dodges people raising other gun control-related suggestions. Indeed, a look at the NRA’s support doesn’t even explicitly call for banning bump-stocks, just to have BATFE re-examine the law to see if they’re actually legal.
Lengthy but interesting article.
How the NRA and the far-right are quietly mobilizing to kill gun safety reform after Vegas
If you’re talking about bump stocks, you don’t have to talk about assault rifles.
This article has a bit more about all this. It paints it as more of a desperation move on the NRA's part, and also goes a bit more into the ATF's prior review of bump-stocks.
https://www.washingtonpost.com/news/the-fix/wp/2017/10/05/the-nras-game-changing-and-conveniently-spun-statement-against-bump-stocks/?utm_term=.e83e6bb15776